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Olanzapine
(Copyright 1998 - Mosby, Inc.)
Categories: Psychotic Disorders; Schizophrenia; Pregnancy Category C; FDA Approved 1996 Sep
FDA Drug Class: Antipsychotics/Antimanics
Brand Names: Zyprexa
Description
Clinical Pharmacology
Clinical Studies
Indications and Usage
Contraindications
Warnings
Precautions
Drug Interactions
Adverse Reactions
Drug Abuse and Dependence
Overdosage
Dosage and Administration
Animal Pharmacology
How Supplied
Olanzapine is an antipsychotic agent that belongs to the thienobenzodiazepine class. The chemical designation is 2-methyl-4-(4-methyl-1-piperazinyl)-l OH-thieno[2,3-b] [1,5] benzodiazepine. The molecular formula is C17H20N4S, which corresponds to a molecular weight of 312.44.
Olanzapine is a yellow crystalline solid, which is practically insoluble in water.
Olanzapine tablets are intended for oral administration only.
Each Zyprexa tablet contains olanzapine equivalent to 5 mg (16 
mol), 7.5 mg (24 mol), or 10 mg (32mol). Inactive ingredients are carnuba wax, color mixture white,
crospovidone, FD&C Blue No. 2 Aluminum Lake, hydroxypropyl cellulose, hydroxypropyl
methylcellulose, lactose, magnesium stearate, microcrystalline cellulose, and other
inactive ingredients.
Pharmacodynamics: Olanzapine is a selective monoaminergic antagonist with high
affinity binding to the following receptors: serotonin 5HT2A/2C (Ki=4
and 11 nM, respectively), dopamine D1-4 (Ki 11- 31 nM), muscarinic Ml-5
(Ki=1.9-25 nM), histamine H1 (Ki=7 nM), and adrenergic
alpha1 receptors (Ki=19 nM). Olanzapine binds weakly to GABAA,
BZD, and beta adrenergic receptors (Ki>10 M).
The mechanism of action of olanzapine, as with other antipsychotic drugs, is unknown. However, it has been proposed that this drug's antipsychotic activity is mediated through a combination of dopamine and serotonin type 2 (5HT2) antagonism. Antagonism at receptors other than dopamine and 5HT2 with similar receptor affinities may explain some of the other therapeutic and side effects of olanzapine. Olanzapine's antagonism of muscarinic M1- 5 receptors may explain its anticholinergic effects. Olanzapine's antagonism of histamine H1 receptors may explain the somnolence observed with this drug. Olanzapine's antagonism of adrenergic alpha1 receptors may explain the orthostatic hypotension observed with this drug.
Pharmacokinetics: Olanzapine is well absorbed and reaches peak concentrations in approximately 6 hours following an oral dose. It is eliminated extensively by first pass metabolism, with approximately 40% of the dose metabolized before reaching the systemic circulation. Food does not affect the rate or extent of olanzapine absorption.
Olanzapine displays linear kinetics over the clinical dosing range. Its half-life ranges from 21 to 54 hours (5th to 95th percentile; mean of 30 hr), and apparent plasma clearance ranges from 12 to 47 L/hr (5th to 95th percentile; mean of 25 L/hr).
Administration of olanzapine once daily leads to steady-state concentrations in about one week that are approximately twice the concentrations after single doses. Plasma concentrations, half life, and clearance of olanzapine may vary between individuals on the basis of smoking status, gender, and age (see Special Populations).
Olanzapine is extensively distributed throughout the body, with a volume of distribution of approximately 1000 L. It is 93% bound to plasma proteins over the concentration range of 7 to 1100 ng/ml, binding primarily to albumin and alpha1-acid glycoprotein.
Metabolism and Elimination: Following a single oral dose of 14C labeled olanzapine, 7% of the dose of olanzapine was recovered in the urine as unchanged drug, indicating that olanzapine is highly metabolized. Approximately 57% and 30% of the dose was recovered in the urine and feces, respectively. In the plasma, olanzapine accounted for only 12% of the AUC for total radioactivity, indicating significant exposure to metabolites. After multiple dosing, the major circulating metabolites were the 10-N-glucuronide, present at steady state at 44% of the concentration of olanzapine, and 4´-N-desmethyl olanzapine, present at steady state at 31% of the concentration of olanzapine. Both metabolites lack pharmacological activity at the concentrations observed.
Direct glucuronidation and cytochrome P450 (CYP) mediated oxidation are the primary metabolic pathways for olanzapine. In vitro studies suggest that CYPs lA2 and 2D6, and the flavin-containing monooxygenase system are involved in olanzapine oxidation. CYP2D6 mediated oxidation appears to be a minor metabolic pathway in vivo, because the clearance of olanzapine is not reduced in subjects who are deficient in this enzyme.
Renal Impairment: Because olanzapine is highly metabolized before excretion and only 7% of the drug is excreted unchanged, renal dysfunction alone is unlikely to have a major impact on the pharmacokinetics of olanzapine. The pharmacokinetic characteristics of olanzapine were similar in patients with severe renal impairment and normal subjects, indicating that dosage adjustment based upon the degree of renal impairment is not required. In addition, olanzapine is not removed by dialysis. The effect of renal impairment on metabolite elimination has not been studied.
Hepatic Impairment: Although the presence of hepatic impairment may be expected to reduce the clearance of olanzapine, a study of the effect of impaired liver function in subjects (n=6) with clinically significant (Childs Pugh Classification A and B) cirrhosis revealed little effect on the pharmacokinetics of olanzapine.
Age: In a study involving 24 healthy subjects, the mean elimination half-life of olanzapine was about 1.5 times greater in elderly (>65 years) than in non-elderly subjects (<=65 years). Caution should be used in dosing the elderly, especially if there are other factors that might additively influence drug metabolism and/or pharmacodynamic sensitivity (see DOSAGE AND ADMINISTRATION).
Gender: Clearance of olanzapine is approximately 30% lower in women than in men. There were, however, no apparent differences between men and women in effectiveness or adverse effects. Dosage modifications based on gender should not be needed.
Smoking Status: Olanzapine clearance is about 40% higher in smokers than in nonsmokers, although dosage modifications are not routinely recommended.
Race: No specific pharmacokinetic study was conducted to investigate the effects of race. A cross-study comparison between data obtained in Japan and data obtained in the US suggests that exposure to olanzapine may be about 2-fold greater in the Japanese when equivalent doses are administered. Clinical trial safety and efficacy data, however, did not suggest clinically significant differences among Caucasian patients, patients of African descent, and a third pooled category including Asian and Hispanic patients. Dosage modifications for race are, therefore, not recommended.
Combined Effects: The combined effects of age, smoking, and gender could lead to substantial pharmacokinetic differences in populations. The clearance in young smoking males, for example, may be 3 times higher than that in elderly nonsmoking females. Dosing modification may be necessary in patients who exhibit a combination of factors that may result in slower metabolism of olanzapine (see DOSAGE AND ADMINISTRATION).
Clinical Efficacy Data: The efficacy of olanzapine in the management of the manifestations of psychotic disorders was established in 2 short-term (6-week) controlled trials of psychotic inpatients who met DSM III-R criteria for schizophrenia. A single haloperidol arm was included as a comparative treatment in one of the two trials, but this trial did not compare these two drugs on the full range of clinically relevant doses for both.
Several instruments were used for assessing psychiatric signs and symptoms in these studies, among them the Brief Psychiatric Rating Scale (BPRS), a multi-item inventory of general psychopathology traditionally used to evaluate the effects of drug treatment in psychosis. The BPRS psychosis cluster (conceptual disorganization, hallucinatory behavior, suspiciousness, and unusual thought content) is considered a particularly useful subset for assessing actively psychotic schizophrenic patients. A second traditional assessment, the Clinical Global Impression (CGI), reflects the impression of a skilled observer, fully familiar with the manifestations of schizophrenia, about the overall clinical state of the patient. In addition, two more recently developed but less well evaluated scales were employed; these included the 30 item Positive and Negative Symptoms Scale (PANSS), in which is embedded the 18 items of the BPRS, and the Scale for Assessing Negative Symptoms (SANS). The trial summaries below focus on the following outcomes: PANSS total and/or BPRS total; BPRS psychosis cluster; PANSS negative subscale or SANS; and CGI Severity. The results of the trials follow:
In a 6-week, placebo-controlled trial (n=149) involving two fixed olanzapine doses of 1 and 10 mg/day (once daily schedule), olanzapine, at 10 mg/day (but not at 1 mg/day), was superior to placebo on the PANSS total score (also on the extracted BPRS total), on the BPRS psychosis cluster, on the PANSS Negative subscale, and on CGI Severity.
In a 6-week, placebo-controlled trial (n=253) involving 3 fixed dose ranges of olanzapine (5.0±2.5 mg/day, 10.0±2.5 mg/day, and 15.0±2.5 mg/day) on a once daily schedule, the two highest olanzapine dose groups (actual mean doses of 12 and 16 mg/day, respectively) were superior to placebo on BPRS total score, BPRS psychosis cluster, and CGI severity score; the highest olanzapine dose group was superior to placebo on the SANS. There was no clear advantage for the high dose group over the medium dose group.
Examination of population subsets (race and gender) did not reveal any differential responsiveness on the basis of these subgroupings.
Olanzapine is indicated for the management of the manifestations of psychotic disorders.
The antipsychotic efficacy of olanzapine was established in short-term (6-week) controlled trials of schizophrenic inpatients (see CLINICAL STUDIES).
The effectiveness of olanzapine in long-term use, that is, for more than 6 weeks, has not been systematically evaluated in controlled trials. Therefore, the physician who elects to use olanzapine for extended periods should periodically re-evaluate the long-term usefulness of the drug for the individual patient (see DOSAGE AND ADMINISTRATION).
Olanzapine is contraindicated in patients with a known hypersensitivity to the product.
Neuroleptic Malignant Syndrome (NMS): A potentially fatal symptom complex sometimes referred to as Neuroleptic Malignant Syndrome (NMS) has been reported in association with administration of antipsychotic drugs. Clinical manifestations of NMS are hyperpyrexia, muscle rigidity, altered mental status and evidence of autonomic instability (irregular pulse or blood pressure, tachycardia, diaphoresis and cardiac dysrhythmia). Additional signs may include elevated creatinine phosphokinase, myoglobinuria (rhabdomyolysis), and acute renal failure.
The diagnostic evaluation of patients with this syndrome is complicated. In arriving at a diagnosis, it is important to exclude cases where the clinical presentation includes both serious medical illness (e.g., pneumonia, systemic infection, etc.) and untreated or inadequately treated extrapyramidal signs and symptoms (EPS). Other important considerations in the differential diagnosis include central anticholinergic toxicity, heat stroke, drug fever, and primary central nervous system pathology.
The management of NMS should include: l) immediate discontinuation of antipsychotic drugs and other drugs not essential to concurrent therapy; 2) intensive symptomatic treatment and medical monitoring; and 3) treatment of any concomitant serious medical problems for which specific treatments are available. There is no general agreement about specific pharmacological treatment regimens for NMS.
If a patient requires antipsychotic drug treatment after recovery from NMS, the potential reintroduction of drug therapy should be carefully considered. The patient should be carefully monitored, since recurrences of NMS have been reported.
Tardive Dyskinesia: A syndrome of potentially irreversible, involuntary, dyskinetic movements may develop in patients treated with antipsychotic drugs. Although the prevalence of the syndrome appears to be highest among the elderly, especially elderly women, it is impossible to rely upon prevalence estimates to predict, at the inception of antipsychotic treatment, which patients are likely to develop the syndrome. Whether antipsychotic drug products differ in their potential to cause tardive dyskinesia is unknown.
The risk of developing tardive dyskinesia and the likelihood that it will become irreversible are believed to increase as the duration of treatment and the total cumulative dose of antipsychotic drugs administered to the patient increase. However, the syndrome can develop, although much less commonly, after relatively brief treatment periods at low doses.
There is no known treatment for established cases of tardive dyskinesia, although the syndrome may remit, partially or completely, if antipsychotic treatment is withdrawn. Antipsychotic treatment, itself, however, may suppress (or partially suppress) the signs and symptoms of the syndrome and thereby may possibly mask the underlying process. The effect that symptomatic suppression has upon the long-term course of the syndrome is unknown.
Given these considerations, olanzapine should be prescribed in a manner that is most likely to minimize the occurrence of tardive dyskinesia. Chronic antipsychotic treatment should generally be reserved for patients (1) who suffer from a chronic illness that is known to respond to antipsychotic drugs, and (2) for whom altemative, equally effective, but potentially less harmful treatments are not available or appropriate. In patients who do require chronic treatment, the smallest dose and the shortest duration of treatment producing a satisfactory clinical response should be sought. The need for continued treatment should be reassessed periodically.
If signs and symptoms of tardive dyskinesia appear in a patient on olanzapine, drug discontinuation should be considered. However, some patients may require treatment with olanzapine despite the presence of the syndrome.
Orthostatic Hypotension: Olanzapine may induce orthostatic hypotension associated with dizziness, tachycardia, and in some patients, syncope, especially during the initial dose-titration period, probably reflecting its alpha1-adrenergic antagonistic properties. Syncope was reported in 0.6% (15/2500) of olanzapine-treated patients in phase 2-3 studies. The risk of orthostatic hypotension and syncope may be minimized by initiating therapy with 5 mg daily (see DOSAGE AND ADMINISTRATION). A more gradual titration to the target dose should be considered if hypotension occurs. Olanzapine should be used with particular caution in patients with known cardiovascular disease (history of myocardial infarction or ischemia, heart failure, or conduction abnormalities), cerebrovascular disease, and conditions which would predispose patients to hypotension (dehydration, hypovolemia, and treatment with antihypertensive medications).
Seizures: During premarketing testing, seizures occurred in 0.9% (22/2500) of olanzapine treated patients. There were confounding factors that may have contributed to the occurrence of seizures in many of these cases. Olanzapine should be used cautiously in patients with a history of seizures or with conditions that potentially lower the seizure threshold (e.g., Alzheimer's dementia). Conditions that lower the seizure threshold may be more prevalent in a population of 65 years or older.
Hyperprolactinemia: As with other drugs that antagonize dopamine D2 receptors, olanzapine elevates prolactin levels and a modest elevation persists during chronic administration. Tissue culture experiments indicate that approximately one-third of human breast cancers are prolactin dependent in vitro, a factor of potential importance if the prescription of these drugs is contemplated in a patient with previously detected breast cancer of this type. Although disturbances such as galactorrhea, amenorrhea, gynecomastia, and impotence have been reported with prolactin-elevating compounds, the clinical significance of elevated serum prolactin levels is unknown for most patients. As is common with compounds which increase prolactin release, an increase in mammary gland neoplasia was observed in the olanzapine carcinogenicity studies conducted in mice and rats (see Carcinogenesis). However, neither clinical studies nor epidemiologic studies have shown an association between chronic administration of this class of drugs and tumorigenesis in humans; the available evidence is considered too limited to be conclusive.
Transaminase Elevations: In placebo-controlled studies, clinically significant ALT (SGPT) elevations (>=3 times the upper limit of the normal range) were observed in 2% (6/243) of patients exposed to olanzapine compared to none (0/115) of the placebo patients. None of these patients experienced jaundice. In two of these patients, liver enzymes decreased toward normal despite continued treatment and in two others, enzymes decreased upon discontinuation of olanzapine. In the remaining two patients, one, seropositive for hepatitis C, had persistent enzyme elevation for four months after discontinuation, and the other had insufficient follow-up to determine if enzymes normalized.
Within the larger premarketing database of about 2400 patients with baseline SGPT <=90 IU/L, the incidence of SGPT elevation to >200 IU/L was 2% (50/2381). Again, none of these patients experienced jaundice or other symptoms attributable to liver impairment and most had transient changes that tended to normalize while olanzapine treatment was continued.
Among all 2500 patients in clinical trials, about 1% (23/2500) discontinued treatment due to transaminase increases.
Caution should be exercised in patients with signs and symptoms of hepatic impairment, in patients with pre-existing conditions associated with limited hepatic functional reserve, and in patients who are being treated with potentially hepatotoxic drugs. Periodic assessment of transaminases is recommended in patients with significant hepatic disease (see Laboratory Tests).
Potential for Cognitive and Motor Impairment: Somnolence was a commonly reported adverse event associated with olanzapine treatment, occurring at an incidence of 26% in olanzapine patients compared to 15% in placebo patients. This adverse event was also dose related. Somnolence led to discontinuation in 0.4% (9/2500) of patients in the premarketing database.
Since olanzapine has the potential to impair judgment, thinking, or motor skills, patients should be cautioned about operating hazardous machinery, including automobiles, until they are reasonably certain that olanzapine therapy does not affect them adversely.
Body Temperature Regulation: Disruption of the body's ability to reduce core body temperature has been attributed to antipsychotic agents. Appropriate care is advised when prescribing olanzapine for patients who will be experiencing conditions which may contribute to an elevation in core body temperature (e.g., exercising strenuously, exposure to extreme heat, receiving concomitant medication with anticholinergic activity, or being subject to dehydration).
Dysphagia: Esophageal dysmotility and aspiration have been associated with antipsychotic drug use. Two olanzapine-treated patients in a study of olanzapine in Alzheimer's dementia died from aspiration pneumonia. One of these patients had experienced dysphagia prior to the development of aspiration pneumonia. Aspiration pneumonia is a common cause of morbidity and mortality in patients with advanced Alzheimer's dementia. Olanzapine and other antipsychotic drugs should be used cautiously in patients at risk for aspiration pneumonia.
Suicide: The possibility of a suicide attempt is inherent in schizophrenia, and close supervision of high-risk patients should accompany drug therapy. Prescriptions for olanzapine should be written for the smallest quantity of tablets consistent with good patient management, in order to reduce the risk of overdose.
Use in Patients with Concomitant Illness: Clinical experience with olanzapine in patients with certain concomitant systemic illnesses Special Populations, Renal Impairment and Hepatic Impairment is limited.
Olanzapine exhibits in vitro muscarinic receptor affinity. In premarketing clinical trials with olanzapine, olanzapine was associated with constipation, dry mouth, and tachycardia, all adverse events possibly related to cholinergic antagonism. Such adverse events were not often the basis for discontinuations from olanzapine, but olanzapine should be used with caution in patients with clinically significant prostatic hypertrophy, narrow angle glaucoma, or a history of paralytic ileus.
Olanzapine has not been evaluated or used to any appreciable extent in patients with a recent history of myocardial infarction or unstable heart disease. Patients with these diagnoses were excluded from premarketing clinical studies. Because of the risk of orthostatic hypotension with olanzapine, caution should be observed in cardiac patients (see PRECAUTIONS, Orthostatic Hypotension).
Physicians are advised to discuss the following issues with patients for whom they prescribe olanzapine:
Orthostatic Hypotension: Patients should be advised of the risk of orthostatic hypotension, especially during the period of initial dose titration and in association with the use of concomitant drugs that may potentiate the orthostatic effect of olanzapine, (e.g., diazepam or alcohol) (see DRUG INTERACTIONS).
Interference with Cognitive and Motor Performance: Because olanzapine has the potential to impair judgment, thinking, or motor skills, patients should be cautioned about operating hazardous machinery, including automobiles, until they are reasonably certain that olanzapine therapy does not affect them adversely.
Pregnancy: Patients should be advised to notify their physician if they become pregnant or intend to become pregnant during therapy with olanzapine.
Nursing: Patients should be advised not to breast-feed an infant if they are taking olanzapine.
Concomitant Medication: Patients should be advised to inform their physicians if they are taking, or plan to take, any prescription or over-the-counter drugs, since there is a potential for interactions.
Alcohol: Patients should be advised to avoid alcohol while taking olanzapine.
Heat Exposure and Dehydration: Patients should be advised regarding appropriate care in avoiding overheating and dehydration.
Periodic assessment of transaminases is recommended in patients with significant hepatic disease (see PRECAUTIONS, Transaminase Elevations).
Carcinogenesis: Oral carcinogenicity studies were conducted in mice and rats. Olanzapine was administered to mice in two 78-week studies at doses of 3, 10, 30/20 mg/kg/day (equivalent to 0.8-5 times the maximum recommended human daily dose on a mg/m2 basis) and 0.25, 2, 8 mg/kg/day (equivalent to 0.06-2 times the maximum recommended human daily dose on a mg/m2 basis). Rats were dosed for 2 years at doses of 0.25, 1, 2.5, 4 mg/kg/day (males) and 0.25, 1, 4, 8 mg/kg/day (females) (equivalent to 0.13-2 and 0.13-4 times the maximum recommended human daily dose on a mg/m2 basis, respectively). The incidence of liver hemangiomas and hemangiosarcomas was significantly increased in one mouse study in female mice dosed at 8 mg/kg/day (2 times the maximum recommended human daily dose on a mg/m2 basis). These tumors were not increased in another mouse study in females dosed at 10 or 30/20 mg/l g/day (2-5 times the maximum recommended human daily dose on a mg/m2 basis); in this study, there was a high incidence of early mortalities in males of the 30/20 mg/kg/day group. The incidence of mammary gland adenomas and adenocarcinomas was significantly increased in female mice dosed at >=2 mg/kg/day and in female rats dosed at >=4 mg/kg/day (0.5 and 2 times the maximum recommended human daily dose on a mg/m2 basis, respectively). Antipsychotic drugs have been shown to chronically elevate prolactin levels in rodents. Serum prolactin levels were not measured during the olanzapine carcinogenicity studies; however, measurements during subchronic toxicity studies showed that olanzapine elevated serum prolactin levels up to 4-fold in rats at the same doses used in the carcinogenicity study. An increase in mammary gland neoplasms has been found in rodents after chronic administration of other antipsychotic drugs and is considered to be prolactin mediated. The relevance for human risk of the finding of prolactin mediated endocrine tumors in rodents is unknown (see PRECAUTIONS, General, Hyperprolactinemia).
Mutagenesis: No evidence of mutagenic potential for olanzapine was found in the Ames reverse mutation test, in vivo micronucleus test in mice, the chromosomal aberration test in Chinese hamster ovary cells, unscheduled DNA synthesis test in rat hepatocytes, induction of forward mutation test in mouse lymphoma cells, or in vivo sister chromatid exchange test in bone marrow of Chinese hamsters.
Impairment of Fertility: In a fertility and reproductive performance study in rats, male mating performance, but not fertility, was impaired at a dose of 22.4 mg/kg/day and female fertility was decreased at a dose of 3 mg/kg/day (11 and l.5 times the maximum recommended human daily dose on a mg/m2 basis, respectively.). Discontinuance of olanzapine treatment reversed the effects on male mating performance. In female rats, the precoital period was increased and the mating index reduced at 5 mg/kg/day (2.5 times the maximum recommended human daily dose on a mg/m2 basis). Diestrous was prolonged and estrous delayed at 1.1 mg/kg/day (0.6 times the maximum recommended human daily dose on a mg/m2 basis); therefore olanzapine may produce a delay in ovulation.
In reproduction studies in rats at doses up to 18 mg/kg/day and in rabbits at doses up to 30 mg/kg/day (9 and 30 times the maximum recommended human daily dose on a mg/m2 basis, respectively) no evidence of teratogenicity was observed. In a rat teratology study, early resorptions and increased numbers of nonviable fetuses were observed at a dose of 18 mg/kg/day (9 times the maximum recommended human daily dose on a mg/m2 basis). Gestation was prolonged at 10 mg/kg/day (5 times the maximum recommended human daily dose on a mg/m2 basis). In a rabbit teratology study, fetal toxicity (manifested as increased resorptions and decreased fetal weight) occurred at a maternally toxic dose of 30 mg/kg/day (30 times the maximum recommended human daily dose on a mg/m2 basis).
Placental transfer of olanzapine occurs in rat pups.
There are no adequate and well-controlled trials with olanzapine in pregnant females. Seven pregnancies were observed during clinical trials with olanzapine, including 2 resulting in normal births, 1 resulting in neonatal death due to a cardiovascular defect, 3 therapeutic abortions, and 1 spontaneous abortion. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Parturition in rats was not affected by olanzapine. The effect of olanzapine on labor and delivery in humans is unknown.
Olanzapine was excreted in milk of treated rats during lactation. It is not known if olanzapine is excreted in human milk. It is recommended that women receiving olanzapine should not breast-feed.
Safety and effectiveness in pediatric patients below 18 years of age have not been established.
Of the 2500 patients in clinical studies with olanzapine, 11% (263) were 65 years of age or over. In general, there was no indication of any different tolerability of olanzapine in the elderly compared to younger adults. Nevertheless, the presence of factors that might decrease pharmacokinetic clearance or increase the pharmacodynamic response to olanzapine should lead to consideration of a lower starting dose (see PRECAUTIONS and DOSAGE AND ADMINISTRATION).
The risks of using olanzapine in combination with other drugs have not been extensively evaluated in systematic studies. Given the primary CNS effects of olanzapine, caution should be used when olanzapine is taken in combination with other centrally acting drugs and alcohol.
Because of its potential for inducing hypotension, olanzapine may enhance the effects of certain antihypertensive agents.
Olanzapine may antagonize the effects of levodopa and dopamine agonists.
The Effect of Other Drugs on Olanzapine: Agents that induce CYP1A2 or glucuronyl transferase enzymes, such as omeprazole and rifampin, may cause an increase in olanzapine clearance. Inhibitors of CYPlA2 (e.g., fluvoxamine) could potentially inhibit olanzapine elimination. Because olanzapine is metabolized by multiple enzyme systems, inhibition of a single enzyme may not appreciably decrease olanzapine clearance.
Charcoal: The administration of activated charcoal (1 g) reduced the Cmax and AUC of olanzapine by about 60%. As peak olanzapine levels are not typically obtained until about 6 hours after dosing, charcoal may be a useful treatment for olanzapine overdose.
Cimetidine and Antacids: Single doses of cimetidine (800 mg) or aluminum- and magnesium-containing antacids did not affect the oral bioavailability of olanzapine.
Carbamazepine: Carbamazepine therapy (200 mg twice daily) causes an approximately 50% increase in the clearance of olanzapine. This increase is likely due to the fact that carbamazepine is a potent inducer of CYPlA2 activity. Higher daily doses of carbamazepine may cause an even greater increase in olanzapine clearance.
Ethanol: Ethanol (45 mg/70 kg single dose) did not have an effect on olanzapine pharmacokinetics .
Warfarin: Warfarin (20 mg single dose) did not affect olanzapine pharmacokinetics.
Effect of Olanzapine on Other Drugs: In vitro studies utilizing human liver microsomes suggest that olanzapine has little potential to inhibit CYPlA2, CYP2C9, CYP2Cl9, CYP2D6, and CYP3A. Thus, olanzapine is unlikely to cause clinically important drug interactions mediated by these enzymes.
Single doses of olanzapine did not affect the pharmacokinetics of imipramine or its active metabolite desipramine, and warfarin. Multiple doses of olanzapine did not influence the kinetics of diazepam and its active metabolite N-desmethyldiazepam, lithium, ethanol, or biperiden. However, the co-administration of either diazepam or ethanol with olanzapine potentiated the orthostatic hypotension observed with olanzapine. Multiple doses of olanzapine did not affect the pharmacokinetics of theophylline or its metabolites.
The premarketing development program for olanzapine included over 3100 patients and/or normal subjects exposed to 1 or more doses of olanzapine. Of these 3100 subjects, 2500 were patients who participated in multiple dose effectiveness trials, and their experience corresponded to approximately 1122 patient-years. The conditions and duration of treatment with olanzapine varied greatly and included (in overlapping categories) open-label and double-blind phases of studies, inpatients and outpatients, fixed-dose and dose-titration studies, and short-term or longer-term exposure. Adverse reactions were assessed by collecting adverse events, results of physical examinations, vital signs, weights, laboratory analytes, ECGs, chest x-rays, and results of ophthalmologic examinations.
Adverse events during exposure were obtained by spontaneous report and recorded by clinical investigators using terminology of their own choosing. Consequently, it is not possible to provide a meaningful estimate of the proportion of individuals experiencing adverse events without first grouping similar types of events into a smaller number of standardized event categories. In the tables and tabulations that follow, standard COSTART dictionary terminology has been used to classify reported adverse events.
The stated frequencies of adverse events represent the proportion of individuals who experienced, at least once, a treatment-emergent adverse event of the type listed. An event was considered treatment emergent if it occurred for the first time or worsened while receiving therapy following baseline evaluation.
The following findings are based on a pool of two 6-week, placebo-controlled trials in which mean olanzapine doses ranged from 7-16 mg/day.
Adverse Events Associated with Discontinuation of Treatment in Short-Term Placebo-Controlled Trials: Overall, there was no difference in the incidence of discontinuation due to adverse events (5% for olanzapine vs 6% for placebo). However, discontinuations due to increases in SGPT were considered to be drug related (2% for olanzapine vs 0% for placebo) (see PRECAUTIONS).
Adverse Events Occurring at an Incidence of 1% or More Among Olanzapine-Treated Patients in Short-Term, Placebo-Controlled Trials: TABLE 1 enumerates the incidence, rounded to the nearest percent, of treatment-emergent adverse events that occurred during acute therapy (up to 6 weeks) of schizophrenia in 1% or more of patients treated with olanzapine (doses >=2.5 mg/day) where the incidence in patients treated with olanzapine was greater than the incidence in placebo treated patients.
The prescriber should be aware that the figures in the tables and tabulations cannot be used to predict the incidence of side effects in the course of usual medical practice where patient characteristics and other factors differ from those that prevailed in the clinical trials. Similarly, the cited frequencies cannot be compared with figures obtained from other clinical investigations involving different treatments, uses, and investigators. The cited figures, however, do provide the prescribing physician with some basis for estimating the relative contribution of drug and nondrug factors to the side effect incidence in the population studied.
8 4 Akathisia 5 1 Hypertonia 4 3
Tremor 4 3 Amnesia 2 0 Articulation impairment 2 0 Euphoria 2 0 Stuttering 2 0 Respiratory
System Rhinitis 10 6 Cough increased 5 3 Pharyngitis 5 3 Skin and Appendages
Vesiculobullous rash 2 1 Special Senses Amblyopia 5 4 Blepharitis 2 1 Corneal
lesion 1 0 Urogenital System Prementrual syndrome
2 0 * Events reported by at least 1% of patients treated with
olanzapine, except the following events which had an incidence equal to or less than
placebo: abnormal dreams, accidental injury, anorexia, apathy, asthenia, cogwheel
rigidity, confusion, conjunctivitis, dental pain, diarrhea, depression, dysmenorrhea, dyspepsia, ecchymosis, emotional
libility, hallucinations, hyperkinesia, hypertension, hypokenesia, joint stiffness, libido
increased, myalgia, nausea, paranoid reaction, paresthesia, pruritus, rash, schizophrenic
reaction, sweating, thinking abnormal, tooth caries, vaginitis, vomiting. 
Personality disorder is the COSTART term for designating
non-aggressive objectionable behavior. Denominator used was for females only (olanzapine, N=41; placebo, N=23).
Commonly Observed Adverse Events in Short-Term, Placebo-Controlled Trials: The most commonly observed adverse events associated with the use of olanzapine (incidence of 5% or greater) and not observed at an equivalent incidence among placebo-treated patients (olanzapine incidence at least twice that for placebo) are in TABLE 2.
15 14 12 14 Akathisia 23 16 19 27 * No statistically significant
differences. Percentage of
patients with a Simpson-Angus Scale total score >3. Percentage of patients with a Barnes Akathisia Scale global
score >=2.
TABLE 4 enumerates the percentage of patients with treatment-emergent extrapyramidal symptoms as assesed by spontaneously reported adverse events during acute therapy in the same controlled clinical trial comparing olanzapine at 3 fixed doses with placebo in the treatment of schizophrenia.
1 3 2 3 Parkinsonism events 10 8 14 20 Akathisia events§ 1 5 11*
10* Dyskinetic events || 4 0 2 1 Residual events¶ 1 2 5 1 Any extrapyramidal event 16 15
25 32* * Statistically significantly different from placebo. Patients with the following COSTART terms were
counted in this category: dystonia, generalized spasm, neck rigidity, oculoyric crisis,
opisthontonos, torticollis.
Patients with the following COSTART terms were counted in this category: akinesia,
cogwheel rigidity, extrapyramidal syndrome, hypertonia, hypokinesia, masked facies,
tremor. § Patients with the following COSTART terms were counted in this category:
akathisia, hyperkinesia. || Patients with the following COSTART terms were counted in this
category: buccoglossal syndrome, choreoathetosis, dyskinesia, tardive dyskinesia. ¶
Patients with the following COSTART terms were counted in this category: movement
disorder, myoclonus, twitching.
Other Adverse Events: TABLE 5 address dose relatedness for other adverse events using data from a trial involving fixed dosage ranges. It enumerates the percentage of patients with treatment-emergent adverse events for the three fixed-dose range groups and placebo. The data were analyzed using the Cochran-Armitage test, excluding the placebo group, and the table includes only those adverse events for which there was a statistically significant trend.
Weight Gain: In placebo-controlled, 6-week studies, weight gain was reported in 5.6% of olanzapine patients compared to 0.8% of placebo patients. Olanzapine patients gained an average of 2.8 kg, compared to an average 0.4 kg weight loss in placebo patients; 29% of olanzapine patients gained greater than 7% of their baseline weight, compared to 3% of placebo patients. A categorization of patients at baseline on the basis of body mass index (BMI) revealed a significantly greater effect in patients with low BMI compared to normal or overweight patients; nevertheless; weight gain was greater in all 3 olanzapine groups compared to the placebo group. During long-term continuation therapy with olanzapine (238 median days of exposure), 56% of olanzapine patients met the criterion for having gained greater than 7% of their baseline weight. Average weight gain during long-term therapy was 5.4 kg.
Laboratory Changes: An assessment of the premarketing experience for olanzapine revealed an association with asymptomatic increases in SGPT, SGOT, and GGT (see PRECAUTIONS). Olanzapine administration was also associated with increases in serum prolactin (see PRECAUTIONS), with an asymptomatic elevation of the eosinophil in 0.3% of patients, and with an increase in CPK.
Given the concern about neutropenia associated with other psychotropic compounds and the finding of leukopenia associated with the administration of olanzapine in several animal models (see ANIMAL PHARMACOLOGY), careful attention was given to examination of hematologic parameters in premarketing studies with olanzapine. There was no indication of a risk of clinically significant neutropenia associated with olanzapine treatment in the premarketing database for this drug.
ECG Changes: Between-group comparisons for pooled placebo-controlled trials revealed no statistically significant olanzapine/placebo differences in the proportions of patients experiencing potentially important changes in ECG parameters, including QT, QTc, and PR intervals. Olanzapine use was associated with a mean increase in heart rate of 2.4 beats per minute compared to no change among placebo patients. This slight tendency to tachycardia may be related to olanzapine's potential for inducing orthostatic changes (see PRECAUTIONS).
Events are further categorized by body system and listed in order of decreasing frequency according to the following definitions: frequent adverse events are those occurring in at least 1/100 patients (only those not already listed in the tabulated results from placebo-controlled trials appear in this listing); infrequent adverse events are those occurring in 1/100 to 1/1000 patients; rare events are those occurring in fewer than 1/1000 patients.
Body as a Whole: Frequent: flu syndrome and suicide attempt; Infrequent: chills, chills and fever, face edema, hangover effect, malaise, moniliasis, neck pain, pelvic pain, and photosensitivity reaction; Rare: abdomen enlarged and sudden death.
Cardiovascular System: Infrequent: cerebrovascular accident, hemorrhage, migraine, palpitation, vasodilatation, and ventricular extrasystoles; Rare: heart arrest.
Digestive System: Frequent: increased salivation, nausea and vomiting, and thirst; Infrequent: aphthous stomatitis, dysphagia, eructation, esophagitis, fecal incontinence, flatulence, gastritis, gastroenteritis, gingivitis, glossitis, hepatitis, melena, mouth ulceration, oral moniliasis, periodontal abscess, rectal hemorrhage, stomatitis, and tongue edema; Rare: enteritis, esophageal ulcer, and tongue discoloration.
Endocrine System: lnfrequent: diabetes mellitus and goiter; Rare: diabetic acidosis.
Hemic and Lymphatic System: Infrequent: cyanosis, leukocytosis, lymphadenopathy, and thrombocythemia.
Metabolic and Nutritional Disorders: Frequent: weight loss; Infrequent: alkaline phosphatase increased, bilirubinemia, dehydration, hyperglycemia, hyperkalemia, hyperuricemia, hypoglycemia, hypokalemia, hyponatremia, ketosis, and water intoxication; Rare: hypercholesteremia and hyperlipemia.
Musculoskeletal System: Infrequent: arthritis, back and hip pain, bursitis, leg cramps, myasthenia, and rheumatoid arthritis; Rare: bone pain and myopathy.
Nervous System: Frequent: tardive dyskinesia; Infrequent: abnormal gait, alcohol misuse, antisocial reaction, ataxia, CNS stimulation, coma, delirium, depersonalization, hypesthesia, hypotonia, incoordination, libido decreased, obsessive compulsive symptoms, phobias, somatization, stimulant misuse, stupor, vertigo, and withdrawal syndrome; Rare: facial paralysis, neuralgia, nystagmus, and subarachnoid hemorrhage.
Respiratory System: Frequent: dyspnea; Infrequent: apnea, asthma, epistaxis, hemoptysis, hyperventilation, and voice alteration; Rare: laryngitis.
Skin and Appendages: Infrequent: alopecia, contact dermatitis, dry skin, eczema hirsutism, seborrhea, skin ulcer, and urticaria; Rare: maculopapular rash and skin discoloration.
Special Senses: Infrequent: cataract, deafness, diplopia, dry eyes, ear pain, eye hemorrhage, eye inflammation, eye pain, ocular muscle abnormality, taste perversion, and tinnitus; Rare: abnormality of accommodation, glaucoma, keratoconjunctivitis, macular hypopigmentation, mydriasis, and pigment deposits lens.
Urogenital System: Frequent: hematuria, metrorrhagia*, urinary incontinence, and urinary tract infection; Infrequent: abnormal ejaculation*, amenorrhea*, breast pain, cystitis, decreased menstruation*, dysuria, increased menstruation*, female lactation, impotence*, menorrhagia*, polyuria, pyuria, urinary retention, urinary frequency, urination impaired, and uterine fibroids enlarged*; Rare: albuminuria.
*Adjusted for gender.
Controlled Substance Class: Olanzapine is not a controlled substance.
Physical and Psychological Dependence: In studies prospectively designed to assess abuse and dependence potential, olanzapine was shown to have acute depressive CNS effects but little or no potential of abuse or physical dependence in rats administered oral doses up to 15 times the maximum daily human dose (20 mg) and rhesus monkeys administered oral doses up to 8 times the maximum daily human dose on a mg/m2 basis.
Olanzapine has not been systematically studied in humans for its potential for abuse, tolerance, or physical dependence. While the clinical trials did not reveal any tendency for any drug-seeking behavior, these observations were not systematic, and it is not possible to predict on the basis of this limited experience the extent to which a CNS-active drug will be misused, diverted, and/or abused once marketed. Consequently, patients should be evaluated carefully for a history of drug abuse, and such patients should be observed closely for signs of misuse or abuse of olanzapine (e.g., development of tolerance, increases in dose, drug-seeking behavior).
Human Experience: In premarketing trials involving more than 3100 patients and/or normal subjects, accidental or intentional acute overdosage of olanzapine was identified in 67 patients. In the patient taking the largest identified amount, 300 mg, the only symptoms reported were drowsiness and slurred speech. In the limited number of patients who were evaluated in hospitals, including the patient taking 300 mg, there were no observations indicating an adverse change in laboratory analytes or ECG. Vital signs were usually within normal limits following overdoses.
Overdosage Management: The possibility of multiple drug involvement should be considered. In case of acute overdosage, establish and maintain an airway and ensure adequate oxygenation and ventilation. Gastric lavage (after intubation, if patient is unconscious) and administration of activated charcoal together with a laxative should be considered. The possibility of obtundation, seizures, or dystonic reaction of the head and neck following overdose may create a risk of aspiration with induced emesis. Cardiovascular monitoring should commence immediately and should include continuous electrocardiographic monitoring to detect possible arrhythmias.
There is no specific antidote to olanzapine. Therefore, appropriate supportive measures should be initiated. Hypotension and circulatory collapse should be treated with appropriate measures such as intravenous fluids and/or sympathomimetic agents. (Do not use epinephrine, dopamine, or other sympathomimetics with beta-agonist activity, since beta stimulation may worsen hypotension in the setting of olanzapine-induced alpha blockade.) Close medical supervision and monitoring should continue until the patient recovers.
Usual Dose: Olanzapine should be administered on a once-a-day schedule without regard to meals, generally beginning with 5 to 10 mg initially, with a target dose of 10 mg/day within several days. Further dosage adjustments, if indicated, should generally occur at intervals of not less than 1 week, since steady state for olanzapine would not be achieved for approximately 1 week in the typical patient. When dosage adjustments are necessary, dose increments/decrements of 5 mg daily are recommended.
Antipsychotic efficacy was demonstrated in a dose range of 10 to 15 mg/day in the clinical trials. However, doses above 10 mg/day were not demonstrated to be more efficacious than the 10 mg/day dose. An increase to a dose greater than target dose of 10 mg/day (i.e., to a dose of 15 mg/day or greater) is recommended only after clinical assessment. The safety of doses above 20 mg/day has not been evaluated in clinical trials.
Dosing in Special Populations: The recommended starting dose is 5 mg in patients who are debilitated, who have a predisposition to hypotensive reactions, who otherwise exhibit a combination of factors that may result in slower metabolism of olanzapine (e.g., nonsmoking female patients >= 65 years of age), or who may be more pharmacodynamically sensitive to olanzapine (see CLINICAL PHARMACOLOGY; also see PRECAUTIONS, Use in Patients with Concomitant Illness and DRUG INTERACTIONS). When indicated, dose escalation should be performed with caution in these patients.
Maintenance Treatment: While there is no body of evidence available to answer the question of how long the patient treated with olanzapine should remain on it, the effectivenss of maintenance treatment is well established for many other antipsychotic drugs. It is recommended that responding patients be continued on olanzapine, but at the lowest dose needed to maintain remission. Patients should be periodically reassessed to determine the need for mainentance treatment.
In animal studies with olanzapine, the peincipal hematologic findings were reversible peripheral cytopenias in individual dogs dosed at 10 mg/kg (17 times the maximum recommended human daily dose on a mg/m2 basis), dose-related decreased in lymphocytes and neutrophils in mice, and lymphopenia in rats. A few dogs treated with 10 mg/kg developed reversible neutropenia and/or reversible hemolytic anemia between 1 and 10 months of treatment. Dose-related decreases in lymphocytes and neutrophils were seen in mice given doses of 10 mg/kg (equal to 2 times the maximum recommended human daily dose on a mg/m2 basis) in studies 3 months' duration. Nonspecific lymphopenia, consistent with decreased body weight gain, occurred in rats receiving 22.5 mg/kg (11 times the maximum recommended human daily dose on a mg/m2 basis) for 6 to 12 months. No evidence of bone marrow cytotoxicity was found in any of the species examined. Bone marrows were normocellular or hypercellular, indicating that the reductions in circulating blood cells were probably due to peripheral (non-marrow) factors.
Zyprexa tablets are white, round, film-coated, and imprinted in blue ink with LILLY and the tablet number: 5 mg imprinted with ``4115'', 7.5 mg imprinted with ``4116'', 10 mg imprinted with ``4117''.
Store at controlled room temperature, 20° to 25°C (68° to 77°F). The USP defines controlled room temperature as a temperature maintained thermostatically that encompasses the usual and customary working environment of 20° to 25°C (68° to 77°F); that results in a mean kinetic temperature calculated to be not more than 25°C; and that allows for excursions between 15° and 30°C (59° and 86°F) that are experienced in pharmacies, hospitals, and warehouses.
Protect from light and moisture.
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