Quetiapine
Antipsychotic — atypical
Indications
SchizophreniaBipolar mania/depressionAugmentation in depression (XR)
Adult dose
Schizophrenia IR: titrate to 300–450 mg/day in 2 doses, max 750 mg. Bipolar depression XR: 300 mg nocte. Augmentation: 150–300 mg.
Common side effects
Sedation (marked low-dose)Postural hypotensionWeight gainDry mouthConstipation
Serious side effects
NMSQT prolongationDiabetesTardive dyskinesia
Contraindications
Concurrent strong CYP3A4 inhibitors (relative)
Monitoring
- Metabolic monitoring; ECG if cardiac risk
Notable interactions
- Strong CYP3A4 inhibitors (clarithromycin, ketoconazole) raise levels
- Inducers (phenytoin, carbamazepine, rifampicin) lower levels
Curated reference based on BNF, Maudsley Prescribing Guidelines and NICE. Verify against current BNF and local guidelines before prescribing.