Seroquel (quetiapine): Uses, Safety and Drug Interactions

Uses and formulation

Seroquel contains quetiapine, an antipsychotic medicine. The linked record concerns a 25 mg immediate-release film-coated tablet, using UK product information. It is a different formulation from prolonged-release Seroquel XL. The reviewed licensed uses include schizophrenia, bipolar manic episodes, bipolar depression, and prevention of further bipolar episodes in people who previously responded to quetiapine. The 25 mg tablet strength alone does not identify the appropriate treatment dose or diagnosis. These indications should not be extrapolated to every country or quetiapine formulation.

Everyday effects and ongoing checks

Sleepiness, dizziness, dry mouth, constipation and a fall in blood pressure on standing are important effects. They can contribute to falls and make driving unsafe. Weight, blood glucose and blood fats need monitoring because metabolic changes may develop during treatment. Tell the prescriber about diabetes, heart rhythm disease, low blood pressure, sleep apnoea, severe constipation or previous low white blood cell counts. Treatment response and the need for ongoing treatment should be reviewed rather than judged only by sedation.

Interactions that need a medicine review

The UK label contraindicates quetiapine with CYP3A4 inhibitors such as certain HIV medicines, azole antifungals, clarithromycin, erythromycin and nefazodone. These medicines can substantially increase quetiapine exposure. Carbamazepine and phenytoin can reduce exposure and effectiveness; changing either medicine requires prescriber oversight. Alcohol and other centrally acting medicines can worsen impairment. Other medicines that affect heart rhythm, lower electrolytes or have anticholinergic effects also need checking. Serotonergic combinations can increase serotonin syndrome risk. Avoid grapefruit juice according to the reviewed information.

When to seek help and special situations

High fever with rigid muscles and altered awareness, severe blistering rash, fainting, or serious constipation with abdominal symptoms requires urgent assessment. Report new self-harm thoughts immediately. Quetiapine is not approved in this UK information for dementia-related psychosis. Pregnancy and breastfeeding need an individual discussion; exposure near birth can cause newborn movement, breathing or feeding problems. The UK label requires a decision between continuing breastfeeding and continuing quetiapine. Abrupt cessation can produce withdrawal symptoms, so do not improvise a stopping schedule from a summary.

Sources

• Seroquel 25 mg tablets - UK SmPC - eMC updated 4 July 2024; text revision June 2024
• Seroquel immediate-release tablets - UK patient leaflet - Leaflet revised May 2025; eMC updated 11 June 2025

Source check: 30 October 2026. This records a source check, not a clinical review by a doctor or pharmacist. Follow the leaflet supplied with your medicine and seek professional advice for personal treatment.