OLANZAPINE
| OLANZAPINE (o-lan'za-peen) Zyprexa, Zyprexa Zydis Classifications: psychotherapeutic agent, antipsychotic, atypical; Therapeutic:antipsychotic, antimanic Prototype: Clozapine Pregnancy Category: C |
Availability
2.5 mg, 5 mg, 7.5 mg, 10 mg, 15 mg tablets; 10 mg, 15 mg, 20 mg orally disintegrating tablets; 10 mg powder for injection
Action
Antipsychotic activity is thought to be due to antagonism for both serotonin 5-HT2A/2C and dopamine D1–4 receptors. May inhibit the CNS presynaptic neuronal reuptake of serotonin and dopamine. Antagonism of alpha-adrenergic receptors results in the adverse effect of orthostatic hypotension.
Therapeutic Effect
Effective antipsychotic activity.
Uses
Management of psychotic disorders, treatment of bipolar disorder, acute agitation (IM).
Unlabeled Uses
Alzheimer's dementia.
Contraindications
Hypersensitivity to olanzapine; abrupt discontinuation, coma, severe CNS depression, subcutaneous or intramuscular injection of olanzapine; tardive dyskinesia; infants, pregnancy (category C), lactation.
Cautious Use
Known cardiovascular disease, neurological disease, stroke, cerebrovascular disease, Parkinson disease, dementia; history of seizures, conditions that predispose to hypotension (i.e., dehydration, hypovolemia); history of syncope; history of breast cancer; Japanese; diabetes mellitus; prostatic hypertrophy; closed-angle glaucoma; paralytic ileus; urinary retention; hepatic or renal impairment, concurrent use of hepatotoxic drugs, jaundice; predisposition to aspiration pneumonia; may increase risk of stroke in elderly patients with dementia; history of or high risk for suicide. Safety and effectiveness in children and adolescents are not established.
Route & Dosage
| Psychotic Disorders Adult: PO Start with 5–10 mg once/d, may increase by 2.5–5 mg qwk until desired response (usual range 10–15 mg/d, max: 20 mg/d) Geriatric: PO Start with 5 mg once/d Bipolar Mania Adult: PO Start with 10–15 mg once/d, may increase by 5 mg q24h if needed Acute Agitation Adult: IM 10 mg, do not repeat more frequently than q2h (max: 30 mg/24h) Geriatric: IM 2.5–5 mg once |
Administration
Oral- Do not push orally disintegrating tablet through blister foil. Peel foil back and remove tablet. Tablet will disintegrate with/without liquid.
Adverse Effects (≥1%)
Body as a Whole: Weight gain, fever, back and chest pain, peripheral and lower extremity edema, joint pain, twitching, premenstrual syndrome. CNS: Somnolence, dizziness, headache, agitation, insomnia, nervousness, hostility, anxiety, personality disorder, akathisia, hypertonia, tremor amnesia, euphoria, stuttering, extrapyramidal symptoms (dystonic events, parkinsonism, akathisia), tardive dyskinesia. CV: Postural hypotension, hypotension, tachycardia. Special Senses: Amblyopia, blepharitis. GI: Abdominal pain, constipation, dry mouth, increased appetite, increased salivation, nausea, vomiting, elevated liver function tests. Metabolic: Hyperglycemia, diabetes mellitus. Urogenital: Premenstrual syndrome, hematuria, urinary incontinence, metrorrhagia. Respiratory: Rhinitis, cough, pharyngitis, dyspnea. Skin: Rash.Interactions
Drug: May enhance hypotensive effects of antihypertensives. May enhance effects of other CNS active drugs, alcohol. Carbamazepine, omeprazole, rifampin may increase metabolism and clearance of olanzapine. Fluvoxamine may inhibit metabolism and clearance of olanzapine.Pharmacokinetics
Absorption: Rapidly from GI tract; 60% reaches systemic circulation. Onset: 15 min IM. Peak: 6 h. Distribution: 93% protein bound, secreted into breast milk of animals (human secretion unknown). Metabolism: In liver (CYP1A2). Elimination: Approximately 57% in urine, 30% in feces. Half-Life: 21–54 h.Nursing Implications
Assessment & Drug Effects
- Monitor diabetics for loss of glycemic control.
- Withhold drug and immediately report S&S of neuroleptic malignant syndrome (see Appendix F); assess for and report S&S of tardive dyskinesia (see Appendix F).
- Lab tests: Periodically monitor ALT, especially in those with hepatic dysfunction or being treated with other potentially hepatotoxic drugs. Periodic blood glucose monitoring.
- Monitor BP and HR periodically. Monitor temperature, especially under conditions such as strenuous exercise, extreme heat, or treatment with other anticholinergic drugs.
- Monitor for seizures, especially in older adults and cognitively impaired persons.
Patient & Family Education
- Carefully monitor blood glucose levels if diabetic.
- Do not drive or engage in potentially hazardous activities until response to drug is known; drug increases risk of orthostatic hypotension and cognitive impairment.
- Learn common adverse effects and possible drug interactions.
- Avoid alcohol and do not take additional medications without informing physician.
- Do not become overheated; avoid conditions leading to dehydration.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug