Atypical antipsychotic (second generation)

Quetiapine

Brand names: Seroquel, Atrolak, Brancico

Quetiapine is a second-generation ('atypical') antipsychotic used in schizophrenia, bipolar disorder and as an adjunct in depression; lower doses are widely used for their sedative effect.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

2 DOSAGE & ADMINISTRATION · Quetiapine tablets, USP can be taken with or without food ( 2.1 ) Indication Initial Dose Recommended Dose Maximum Dose Schizophrenia-Adults (2.2) 25 mg twice daily 150 to 750 mg/day 750 mg/day Schizophrenia-Adolescents (13 to 17 years) (2.2) 25 mg twice daily 400 to 800 mg/day 800 mg/day Bipolar Mania- Adults Monotherapy or as an adjunct to lithium or divalproex (2.2) 50 mg twice daily 400 to 800 mg/day 800 mg/day Bipolar Mania- Children and Adolescents (10 to 17 years), Monotherapy (2.2) 25 mg twice daily 400 to 600 mg/day 600 mg/day Bipolar Depression-Adults (2.2) 50 mg once daily at bedtime 300 mg/day 300 mg/day Geriatric Use: Consider a lower starting dose …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2025-06-27. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It antagonises dopamine D2 and serotonin 5-HT2A (and other) receptors; its prominent sedation reflects strong histamine H1 blockade.

Prescribing in practice

Metabolic effects (weight gain, dyslipidaemia, raised glucose/diabetes), sedation and postural hypotension are common.
It can prolong the QT interval.
As with all antipsychotics, it increases stroke and mortality risk in older people with dementia — use only where justified.

Monitoring

Monitor weight/BMI, lipids, glucose/HbA1c, blood pressure and (where indicated) ECG.

Counselling the patient

Drowsiness and dizziness on standing are common, especially at first.
Attend your metabolic monitoring (weight, blood tests).
Report fainting or palpitations.

Evidence & guidelines

Recommended across psychotic and mood disorders (NICE NG178/CG185), balanced against metabolic risk.

Reference: NICE CG178; NICE NG185; Maudsley Prescribing Guidelines 14th ed.; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Olanzapine · Atypical antipsychotic (second generation)

Pathways