Formulary
Quetiapine: Indications, Dosing, Side Effects and Interactions
Quetiapine is a dopamine D 1 , dopamine D 2 , 5-HT 2 , alpha 1 -adrenoceptor, and histamine-1 receptor antagonist.
MedNext Academy | 9 min read
Quetiapine: Indications, Dosing, Side Effects and Interactions
Quetiapine is a dopamine D 1 , dopamine D 2 , 5-HT 2 , alpha 1 -adrenoceptor, and histamine-1 receptor antagonist.
Drug action
Quetiapine is a dopamine D 1 , dopamine D 2 , 5-HT 2 , alpha 1 -adrenoceptor, and histamine-1 receptor antagonist.
Indications and dose
**Schizophrenia**
- **Adult** (By Mouth Using Immediate-Release Medicines): 25 mg twice daily for day 1, then 50 mg twice daily for day 2, then 100 mg twice daily for day 3, then 150 mg twice daily for day 4, then, adjusted according to response, usual dose 300-450 mg daily in 2 divided doses, the rate of dose titration may need to be slower and the daily dose lower in elderly patients; maximum 750 mg per day.
- **Adult** (By Mouth Using Modified-Release Medicines): 300 mg once daily for day 1, then 600 mg once daily for day 2, then, adjusted according to response, usual dose 600 mg once daily, maximum dose under specialist supervision; maximum 800 mg per day.
- **Elderly** (By Mouth Using Modified-Release Medicines): Initially 50 mg once daily, adjusted according to response. adjusted in steps of 50 mg daily.
**Treatment of mania in bipolar disorder**
- **Adult** (By Mouth Using Immediate-Release Medicines): 50 mg twice daily for day 1, then 100 mg twice daily for day 2, then 150 mg twice daily for day 3, then 200 mg twice daily for day 4, then adjusted in steps of up to 200 mg daily, adjusted according to response, usual dose 400-800 mg daily in 2 divided doses, the rate of dose titration may need to be slower and the daily dose lower in elderly patients; maximum 800 mg per day.
- **Adult** (By Mouth Using Modified-Release Medicines): 300 mg once daily for day 1, then 600 mg once daily for day 2, then, adjusted according to response, usual dose 400-800 mg once daily.
- **Elderly** (By Mouth Using Modified-Release Medicines): Initially 50 mg once daily, adjusted according to response. adjusted in steps of 50 mg daily.
**Treatment of depression in bipolar disorder**
- **Adult** (By Mouth Using Immediate-Release Medicines): 50 mg once daily for day 1, dose to be taken at bedtime, then 100 mg once daily for day 2, then 200 mg once daily for day 3, then 300 mg once daily for day 4, then, adjusted according to response; usual dose 300 mg once daily, the rate of dose titration may need to be slower and the daily dose lower in elderly patients; maximum 600 mg per day.
- **Adult** (By Mouth Using Modified-Release Medicines): 50 mg once daily for day 1, dose to be taken at bedtime, then 100 mg once daily for day 2, then 200 mg once daily for day 3, then 300 mg once daily for day 4, then, adjusted according to response; usual dose 300 mg once daily; maximum 600 mg per day.
**Prevention of mania and depression in bipolar disorder**
- **Adult** (By Mouth Using Immediate-Release Medicines): Continue at the dose effective for treatment of bipolar disorder and adjust to lowest effective dose; usual dose 300-800 mg daily in 2 divided doses.
- **Adult** (By Mouth Using Modified-Release Medicines): Continue at the dose effective for treatment of bipolar disorder and adjust to lowest effective dose; usual dose 300-800 mg once daily.
**Adjunctive treatment of major depression**
- **Adult** (By Mouth Using Modified-Release Medicines): 50 mg once daily for 2 days, dose to be taken at bedtime, then 150 mg once daily for 2 days, then, adjusted according to response, usual dose 150-300 mg once daily.
- **Elderly** (By Mouth Using Modified-Release Medicines): Initially 50 mg once daily for 3 days, then increased if necessary to 100 mg once daily for 4 days, then adjusted in steps of 50 mg, adjusted according to response, usual dose 50-300 mg once daily, dose of 300 mg should not be reached before day 22 of treatment.
**Schizophrenia for quetiapine**
- **Child 12-17 years (under expert supervision)** (By mouth using immediate-release medicines): Initially 25 mg twice daily, adjusted according to response. adjusted in steps of 25-50 mg; maximum 750 mg per day.
- **Child 12-17 years (under expert supervision)** (By mouth using modified-release medicines): Initially 50 mg once daily, adjusted according to response. adjusted in steps of 50 mg daily, usual dose 400-800 mg once daily; maximum 800 mg per day.
**Treatment of mania in bipolar disorder for quetiapine**
- **Child 12-17 years (under expert supervision)** (By mouth using immediate-release medicines): 25 mg twice daily for day 1, then 50 mg twice daily for day 2, then 100 mg twice daily for day 3, then 150 mg twice daily for day 4, then 200 mg twice daily for day 5, then adjusted in steps of up to 100 mg daily, adjusted according to response, usual dose 400-600 mg daily in 2 divided doses.
Cautions
For all antipsychotic drugs Blood dyscrasias; cardiovascular disease; conditions predisposing to seizures; depression; diabetes (may raise blood glucose); epilepsy; history of jaundice; myasthenia gravis; Parkinson's disease (may be exacerbated); photosensitisation (may occur with higher dosages); prostatic hypertrophy; severe respiratory disease; susceptibility to angle-closure glaucoma Cautions, further information Cardiovascular disease An ECG may be required, particularly if physical examination identifies cardiovascular risk factors, personal history of cardiovascular disease, or if the patient is being admitted as an inpatient. Elderly Screening Tool of Older Persons' potentially inappropriate Prescriptions (STOPP) criteria to aid medication reviews (see Prescribing in the elderly for information). Potentially inappropriate: for all antipsychotics (other than quetiapine and clozapine) in patients with parkinsonism or Lewy Body Disease (risk of severe extrapyramidal symptoms) in behavioural and psychological symptoms of dementia (BPSD), unless symptoms are severe and other non-pharmacological treatments have failed (increased risk of stroke) for use as a hypnotic, unless sleep disorder is due to psychosis or dementia (risk of confusion, hypotension, extrapyramidal side-effects, and falls) in patients prone to falls (may cause gait dyspraxia, parkinsonism) if prescribed a phenothiazine (other than prochlorperazine for nausea, vomiting, or vertigo; chlorpromazine for relief of persistent hiccups; levomepromazine as an antiemetic in palliative care) as first-line treatment (sedative, significant antimuscarinic (anticholinergic) toxicity in older people, and safer and more efficacious alternatives exist) if prescribed an antipsychotic drug with moderate or marked antimuscarinic effects (e.g. chlorpromazine, clozapine, flupenthixol, fluphenazine, pipothiazine, promazine, and zuclopenthixol) in patients with a history of prostatism or urinary retention (high risk of urinary retention) Cautions For quetiapine Cerebrovascular disease; elderly; history or risk factors for sleep apnoea; patients at risk of aspiration pneumonia; treatment of depression in patients under 25 years (increased risk of suicide)
Side effects
For all antipsychotic drugs Common or very common Agitation; amenorrhoea; arrhythmias; constipation; dizziness; drowsiness; dry mouth; erectile dysfunction; fatigue; galactorrhoea; gynaecomastia; hyperglycaemia; hyperprolactinaemia; hypersalivation; hypotension (dose-related); insomnia; leucopenia; movement disorders; muscle rigidity; neutropenia; parkinsonism; postural hypotension (dose-related); QT interval prolongation; rash; seizure; tremor; urinary retention; vomiting; weight increased Uncommon Agranulocytosis; confusion; neuroleptic malignant syndrome (discontinue-potentially fatal) Rare or very rare Sudden death; withdrawal syndrome neonatal Side-effects, further information For depot antipsychotics-side-effects may persist until the drug has been cleared from its depot site. Overdose Phenothiazines cause less depression of consciousness and respiration than other sedatives. Hypotension, hypothermia, sinus tachycardia, and arrhythmias may complicate poisoning. For details on the management of poisoning see Antipsychotics under Emergency treatment of poisoning . Side-effects For quetiapine Common or very common Appetite increased; asthenia; dysarthria; dyspepsia; dyspnoea; fever; headache; irritability; palpitations; peripheral oedema; rhinitis; sleep disorders; suicidal behaviours; syncope; vision blurred; withdrawal syndrome Uncommon Anaemia; diabetes mellitus; dysphagia; hyponatraemia; hypothyroidism; sexual dysfunction; skin reactions; thrombocytopenia Rare or very rare Angioedema; breast swelling; gastrointestinal disorders; hepatic disorders; hypothermia; menstrual disorder; metabolic syndrome; pancreatitis; rhabdomyolysis; severe cutaneous adverse reactions (SCARs); SIADH; venous thromboembolism Frequency not known Sleep apnoea
Interactions
**Severe interactions:**
- Quetiapine should be used with caution in combination with serotonergic medicinal products, such as MAO inhibitors, selective serotonin re-uptake inhibitors (SSRIs), serotonin norepinephrine...
- In a multiple dose trial in patients to assess the pharmacokinetics of quetiapine given before and during treatment with carbamazepine (a known hepatic enzyme inducer), co-administration of...
- The pharmacokinetics of quetiapine were not significantly altered by coadministration of the antidepressants imipramine (a known CYP 2D6 inhibitor) or fluoxetine (a known CYP 3A4 and CYP 2D6...
- The pharmacokinetics of quetiapine were not significantly altered by coadministration of the antipsychotics risperidone or haloperidol.
**Other interactions (16):**
- Given the primary central nervous system effects of quetiapine, quetiapine should be used with caution in combination with other centrally acting medicinal products and alcohol.
- Cytochrome P450 (CYP) 3A4 is the enzyme that is primarily responsible for the cytochrome P450 mediated metabolism of quetiapine.
- In an interaction study in healthy volunteers, concomitant administration of quetiapine (dosage of 25 mg) with ketoconazole, a CYP3A4 inhibitor, caused a 5- to 8-fold increase in the AUC of...
- It is also not recommended to consume grapefruit juice while on quetiapine therapy.
- This increase in clearance reduced systemic quetiapine exposure (as measured by AUC) to an average of 13% of the exposure during administration of quetiapine alone; although a greater effect was...
- As a consequence of this interaction, lower plasma concentrations can occur, which could affect the efficacy of quetiapine therapy.
Pregnancy
For all antipsychotic drugs Extrapyramidal effects and withdrawal syndrome have been reported occasionally in the neonate when antipsychotic drugs are taken during the third trimester of pregnancy. Following maternal use of antipsychotic drugs in the third trimester, neonates should be monitored for symptoms including agitation, hypertonia, hypotonia, tremor, drowsiness, feeding problems, and respiratory distress. Pregnancy For quetiapine Use only if potential benefit outweighs risk.
Breast feeding
For all antipsychotic drugs There is limited information available on the short- and long-term effects of antipsychotic drugs on the breast-fed infant. Animal studies indicate possible adverse effects of antipsychotic medicines on the developing nervous system. Chronic treatment with antipsychotic drugs whilst breast-feeding should be avoided unless absolutely necessary. Phenothiazine derivatives are sometimes used in breast-feeding women for short-term treatment of nausea and vomiting. Breast feeding For quetiapine Manufacturer advises avoid.
Hepatic impairment
Manufacturer advises caution (risk of increased plasma concentrations). Dose adjustments Manufacturer advises for immediate-release tablets , initially 25 mg daily, increased daily in steps of 25-50 mg. Manufacturer advises for modified-release tablets , initially 50 mg daily, increased daily in steps of 50 mg.
Medicinal forms
Solution,Tablet,Tablet,Suspension
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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