Dizziness quetiapine

Quetiapine dizziness, cataracts, mild transient transaminase elevations. 

Quetiapine (Seroquel). Another atypical antipsychotic, quetiapine has also been approved by the FDA for the treatment of acute mania. It is usually administered twice daily at doses of 150-750mg/day. Like its counterparts, quetiapine is a well-tolerated medication. Its common side effects are drowsiness, dizziness, and headache. It causes less weight gain than olanzapine or clozapine but more than ziprasidone or aripiprazole. Quetiapine also does not cause agranulocytosis nor does it increase the risk of seizures. It can occasionally cause mild changes in liver function tests, but these usually return to normal even if the patient continues taking quetiapine. 

Cardiovascular effects. Given aj-adrenergic receptor antagonism, quetiapine may induce orthostatic hypotension and concomitant symptoms of dizziness, tachycardia, and syncope. The risk of symptomatic hypotension is particularly pronounced during initial dose titration. Quetiapine should be used with caution in patients with cardiovascular disease, cerebrovascular disease, or other illnesses predisposing to hypotension. 

Quetiapine (3) has the lowest affinity for the D2 and 5-HT2a receptors among the atypicals therefore, relatively high doses are required for maximal efficacy. Quetiapine causes significant weight gain, but less than that of olanzapine. Other side-effects include sedation, dizziness and hypotension. 

Data from short-term clinical trials (6 weeks) suggest that quetiapine may be useful for the management of psychotic disorders in patients who do not tolerate the adverse effects of the typical antipsychotic drugs or clozapine (3). The most common adverse effects of quetiapine were dizziness, hypotension, somnolence, and weight gain. Raised hepatic enzymes have also been reported. In addition, two patients with idiopathic Parkinson s disease and psychosis were treated with quetiapine for 52 weeks (4). Psychotic symptoms were successfully controlled without worsening of motor disability. 

A 36-year-old woman with rapid-cycling bipolar II disorder and premenstrual mood exacerbation was treated as an out-patient with lamotrigine 400 mg/day, clonazepam 0.5 mg tds, and quetiapine 100 mg/day. She gained 9 kg in 6 months and was advised to reduce the dose of quetiapine to 50 mg/day. After 1 day, she reported nausea, dizziness, headache, and anxiety severe enough to preclude normal daily activities. She was instructed to take quetiapine 75 mg/day, but her symptoms continued and only resolved when she took 100 mg/day. Slower reduction in the dose of quetiapine (by 12.5 mg/day every 5 days) with an antiemetic, ondansetron, also failed. On a third attempt, prochlorperazine successfully reduced her withdrawal symptoms, although moderate nausea persisted for 2 days after complete withdrawal. 

Observational studies In 477 patients with schizophrenia (mean age 38 years), who were switched from their medication to quetiapine (mean median dose 575 mg/ day) because of insufficient efficacy (66%) or insufficient tolerability (34%) in a 12-week, multicenter, open-label study supported by AstraZeneca, the marketing authorization holder of quetiapine common adverse events included somnolence (18%), sedation (15%), and dizziness and dry mouth (14% each), and extrapyramidal symptoms (8.0%) [108 ]. There were higher glucose concentrations both at baseline (n = 8) and end-point (n = 12). The mean body weight change was 1.0 kg. 

Comparative studies Quetiapine and lithium In a 4-week, multicenter, double-blind study, Chinese patients with bipolar mania were randomized to quetiapine (mean dose, 648 mg/day mean age, 33 years n = 11) or lithium (mean serum concentration 0.80 mmol/1 mean age 34 years n = 11) [113 ]. The proportion of patients with at least one adverse event during the study was higher with quetiapine (78%) than lithium (69%). The most common (>5%) adverse events with quetiapine were constipation (35%), dizziness (15%), diarrhea (10%), increased alanine aminotransferase (9.0%), bouts of palpitation (9.0%), increased aspartate aminotransferase (7.7%), pharyngolaryngeal pain (6.4%), upper respiratory tract infections (6.4%), and dry mouth... 

Quetiapine Tablets (Immediate Release = IR) XL tablets Liquid ( ) IR Day 1 psychosis 50 mg mania 100 mg XL tablets start 300 mgod (psychosis /mania) IR Day 2 - 50 mg bd Day 3 100 mg bd Day 4 150 mg bd Then titrate up daily as needed XL day 2 600 mg For depression, see BNF Psychosis 750 mg mania 800 mg Check TFTs Postural drop with initial doses (especially IR) May feel dizzy initially - get up slowly... 

Quetiapine IR at maximal dose (750 mg per day) was compared to oral risperidone in a 6-week, multicenter, randomised, rater single-blind study in Chinese patients with schizophrenia Extrapyramidal symptoms, prolactin levels and upper respiratory infection were significantly lower for quetiapine than for risperidone. Dizziness was significantly higher with quetiapine than with risperidone. Somnolence was greater with quetiapine. 

A 3-week, double-blind, placebo-controlled trial of quetiapine monotherapy in children and adolescents with mania was reported [202 ]. The most common adverse events associated with quetiapine were somnolence, sedation, dizziness and headache most events were mild to moderate in intensity. Potentially clinically relevant increases in total cholesterol, LDL-cholesterol and triglyceride concentrations were more frequent and numericdly larger with quetiapine mean weight gain at end point (observed cases) was 1.7kg for both quetiapine doses and 0.4kg for placebo. 

Observational Studies A naturalistic study of first-episode psychosis outpatients treated with quetiapine reported fatigue, sedation, dizziness, followed by gastrointestinal disorders and nausea and orthostatic hypotension as the most frequent adverse events [203 ]. 

Reviews A review of quetiapine for the treatment of acute bipolar mania, mixed episodes and maintenance therapy reported the most common adverse events in acute trials were somnolence, sedation, dry mouth, weight gain, dizziness, asthenia, pharyngitis and postural hypotension [210 ]. In the maintenance trials, the most common adverse events were somnolence, upper respiratory tract infection, nasopharyngitis and headache. 

A review of quetiapine XR in the treatment of schizophrenia and bipolar disorder is reported to possess similar side effects to quetiapine IR, with the most common being sedation, dry mouth, somnolence, dizziness and headache [21V],... 

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