Olanzapine intramuscular

The risks of using olanzapine in combination with other drugs have not been extensively evaluated in systematic studies. Diazepam: May potentiate orthostatic hypotension. ( 7.1 , 7.2 ) Alcohol: May potentiate orthostatic hypotension. ( 7.1 ) Carbamazepine: Increased clearance of olanzapine. ( 7.1 ) Fluvoxamine: May increase olanzapine levels. ( 7.1 ) CNS Acting Drugs: Caution should be used when taken in combination with other centrally acting drugs and alcohol. ( 7.2 ) Antihypertensive Agents: Enhanced antihypertensive effect. ( 7.2 ) Levodopa and Dopamine Agonists: May antagonize levodopa/dopamine agonists. ( 7.2 ) Lorazepam (IM): Increased somnolence with IM olanzapine.

( 7.2 ) Other Concomitant Drug Therapy: When using olanzapine in combination with lithium or valproate, refer to the Drug Interactions sections of the package insert for those products. ( 7.2 )

7.1 Potential for Other Drugs to Affect Olanzapine Diazepam - The co-administration of diazepam with olanzapine potentiated the orthostatic hypotension observed with olanzapine [see Drug Interactions ( 7.2 )] . Cimetidine and Antacids - Single doses of cimetidine (800 mg) or aluminum- and magnesium-containing antacids did not affect the oral bioavailability of olanzapine. Inducers of CYP1A2 - Carbamazepine therapy (200 mg bid) 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 CYP1A2 activity. Higher daily doses of carbamazepine may cause an even greater increase in olanzapine clearance.

Alcohol - Ethanol (45 mg/70 kg single dose) did not have an effect on olanzapine pharmacokinetics. The co-administration of alcohol (i.e., ethanol) with olanzapine potentiated the orthostatic hypotension observed with olanzapine [see Drug Interactions ( 7.2 )] . Inhibitors of CYP1A2 Fluvoxamine: Fluvoxamine, a CYP1A2 inhibitor, decreases the clearance of olanzapine. This results in a mean increase in olanzapine Cmax following fluvoxamine of 54% in female nonsmokers and 77% in male smokers. The mean increase in olanzapine AUC is 52% and 108%, respectively. Lower doses of olanzapine should be considered in patients receiving concomitant treatment with fluvoxamine.

Inhibitors of CYP2D6 Fluoxetine: Fluoxetine (60 mg single dose or 60 mg daily dose for 8 days) causes a small (mean 16%) increase in the maximum concentration of olanzapine and a small (mean 16%) decrease in olanzapine clearance. The magnitude of the impact of this factor is small in comparison to the overall variability between individuals, and therefore dose modification is not routinely recommended. Warfarin - Warfarin (20 mg single dose) did not affect olanzapine pharmacokinetics [see Drug Interactions ( 7.2 )] . Inducers of CYP1A2 or Glucuronyl Transferase - Omeprazole and rifampin may cause an increase in olanzapine clearance.

Charcoal - The administration of activated charcoal (1 g) reduced the Cmax and AUC of oral 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. Anticholinergic Drugs - Concomitant treatment with olanzapine and other drugs with anticholinergic activity can increase the risk for severe gastrointestinal adverse reactions related to hypomotility. Olanzapine should be used with caution in patients receiving medications having anticholinergic (antimuscarinic) effects [see Warnings and Precautions ( 5.14 )] .

7.2 Potential for Olanzapine to Affect Other Drugs CNS Acting Drugs - Given the primary CNS effects of olanzapine, caution should be used when olanzapine is taken in combination with other centrally acting drugs and alcohol. Antihypertensive Agents - Olanzapine, because of its potential for inducing hypotension, may enhance the effects of certain antihypertensive agents. Levodopa and Dopamine Agonists - Olanzapine may antagonize the effects of levodopa and dopamine agonists.

Lorazepam (IM) - Administration of intramuscular lorazepam (2 mg) 1 hour after intramuscular olanzapine for injection (5 mg) did not significantly affect the pharmacokinetics of olanzapine, unconjugated lorazepam, or total lorazepam. However, this co-administration of intramuscular lorazepam and intramuscular olanzapine for injection added to the somnolence observed with either drug alone [see Warnings and Precautions ( 5.7 )] . Lithium - Multiple doses of olanzapine (10 mg for 8 days) did not influence the kinetics of lithium. Therefore, concomitant olanzapine administration does not require dosage adjustment of lithium [see Warnings and Precautions ( 5.16 )] .

Valproate - Olanzapine (10 mg daily for 2 weeks) did not affect the steady state plasma concentrations of valproate. Therefore, concomitant olanzapine administration does not require dosage adjustment of valproate [see Warnings and Precautions ( 5.16 )] . Effect of Olanzapine on Drug Metabolizing Enzymes - In vitro studies utilizing human liver microsomes suggest that olanzapine has little potential to inhibit CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A. Thus, olanzapine is unlikely to cause clinically important drug interactions mediated by these enzymes. Imipramine - Single doses of olanzapine did not affect the pharmacokinetics of imipramine or its active metabolite desipramine.

Warfarin - Single doses of olanzapine did not affect the pharmacokinetics of warfarin [see Drug Interactions ( 7.1 )] . Diazepam - Olanzapine did not influence the pharmacokinetics of diazepam or its active metabolite N-desmethyldiazepam. However, diazepam co-administered with olanzapine increased the orthostatic hypotension observed with either drug given alone [see Drug Interactions ( 7.1 )] . Alcohol - Multiple doses of olanzapine did not influence the kinetics of ethanol [see Drug Interactions ( 7.1 )] . Biperiden - Multiple doses of olanzapine did not influence the kinetics of biperiden.

Theophylline - Multiple doses of olanzapine did not affect the pharmacokinetics of theophylline or its metabolites.

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to atypical antipsychotics, including Olanzapine, during pregnancy. Healthcare providers are encouraged to register patients by contacting the National Pregnancy Registry for Atypical Antipsychotics at 1-866-961-2388 or visit http://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/. Risk Summary Neonates exposed to antipsychotic drugs, including Olanzapine, during the third trimester are at risk for extrapyramidal and/or withdrawal symptoms following delivery (see Clinical Considerations ).

Overall available data from published epidemiologic studies of pregnant women exposed to olanzapine have not established a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes (see Data ). There are risks to the mother associated with untreated schizophrenia or bipolar I disorder and with exposure to antipsychotics, including Olanzapine, during pregnancy (see Clinical Considerations ).

Olanzapine was not teratogenic when administered orally to pregnant rats and rabbits at doses that are 9- and 30-times the daily oral maximum recommended human dose (MRHD), based on mg/m 2 body surface area; some fetal toxicities were observed at these doses (see Data ). The estimated background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Clinical Considerations Disease-associated maternal and embryo/fetal risk There is a risk to the mother from untreated schizophrenia or bipolar I disorder, including increased risk of relapse, hospitalization, and suicide. Schizophrenia and bipolar I disorder are associated with increased adverse perinatal outcomes, including preterm birth. It is not known if this is a direct result of the illness or other comorbid factors.

Fetal/Neonatal adverse reactions Extrapyramidal and/or withdrawal symptoms, including agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress, and feeding disorder have been reported in neonates who were exposed to antipsychotic drugs, including Olanzapine, during the third trimester of pregnancy. These symptoms have varied in severity. Monitor neonates for extrapyramidal and/or withdrawal symptoms and manage…