Somnolence is a side effect of olanzapine reported with theuse of higher doses of medication. Other frequent side effects on the nervoussystem includes insomnia, dizziness, speech problems, amnesia, apathy, confusion,tremor, paresthesia, agitation, aggression and nervousness. Rarely, cases ofakinesia, abuse of alcohol and stimulants, facial paralysis, tardive dyskinesiaare reported. Possible serious side effects are epileptic seizures, neurolepticmalignant syndrome, somnambulism and Parkinson’s disease.
Side effects on the heart are frequent and includes tachycardia, hypertension (high blood pressure) and postural hypotension,sometimes problems with the heart rhythm, heart failure, migraine, hemorrhage, andpalpitation. In older patients treated for dementia olanzapine slightly increasesthe risk of sudden death or heart failure, and therefore it is not recommended byFDA for use in those cases. In rare cases this medication increases the riskof thromboembolism in elderly patients.
Metabolic changes with the use of olanzapine may includeincrease of appetite and weight gain and food cravings and elevation of triglycerides,lipids, cholesterol and sugar levels in the blood. Olanzapine is connected to some cases ofacidosis, cyanosis, bilirubinemia, dehydratation and hypokalemia andhyponatriemia.
Gastrointestinal problems are common, and those include drymouth, constipation, thirst, vomiting, dyspepsia, sometimes gastritis andgastroenteritis, melena, mouth ulcerations, rectal hemorrhage and intestinalblockage. Nausea and vomiting are side effects that are dose dependant.
Use of olanzapine may affect the liver, increase the levelof liver enzymes, and rarely induce hepatitis, fatty liver or liver injury.
Older dementia patients treated with olanzapine may have an increasedrisk of fatal pneumonia or lower respiratory tract infection.
Olanzapine affects the endocrine system and might induce hyperprolactinemia,hyperglycemia, and diabetes mellitus, rarely fatal diabetic ketoacidosis (maybe fatal) and goiter. It has been proved that that patients on olanzapine areat an increased risk of developing hyperglycemia and diabetes mellitus.
Hematologic side effects are rare and include anemia andproblems with blood cells.
Abnormal vision, conjunctivitis and amblyopia are commonside effects of the olanzapine use. Some accommodation ablormalities, blepharitis,cataract, diplopia, dry eyes, eye hemorrhage, inflammation and pain have beenreported. Rarely there are cases of glaucoma,corneal lesion, keratoconjunctivitis, , miosis, mydriasis, pigment deposits inthe lenses and blepharoclonus.
Extremity pain and joint pain are reported in 5% of thepatient using olanzapine.
Dermatologic side effects might include drug-induced acralmelanosis, eruptive xanthomas, ecchymosis, sweating, acne, and dry skin. Hairloss, seborrhea, contact dermatitis, eczema, rash, urticaria, pruritus, skindiscoloration and ulcer have also been reported, as well as hirsutism, papularrash and a case of hyperpigmentation.
There are serious pshychiatric side effects that come withthe use of olanzapine – depression, euphoria, delusions, and even schizophrenicreaction and suicide attempts.