What is the maximum recommended daily dose of Seroquel (quetiapine)?

Maximum Daily Dose of Seroquel (Quetiapine)

The maximum recommended daily dose of quetiapine is 800 mg/day for schizophrenia and bipolar mania in adults, 600 mg/day for pediatric bipolar mania (ages 10-17), and 300 mg/day for bipolar depression, according to FDA labeling. 1

Standard Maximum Doses by Indication

Adult Dosing

• Schizophrenia: Maximum 750 mg/day 1
• Bipolar Mania (monotherapy or adjunct): Maximum 800 mg/day 1
• Bipolar Depression: Maximum 300 mg/day (administered once daily at bedtime) 1
• Bipolar Maintenance Therapy: Maximum 800 mg/day as adjunct to lithium or divalproex 1

Pediatric Dosing

• Schizophrenia (ages 13-17): Maximum 800 mg/day 1
• Bipolar Mania (ages 10-17): Maximum 600 mg/day 1

Special Population Dose Modifications

Elderly Patients

• Start at 50 mg/day with increments of 50 mg/day based on clinical response 1
• The American Geriatrics Society recommends slower titration rates due to predisposition to hypotensive reactions, with close monitoring for orthostatic hypotension and sedation 2
• Consider that elderly patients have 20-30% higher plasma concentrations and up to 50% lower clearance compared to younger patients 3

Hepatic Impairment

• Start at 25 mg/day with daily increments of 25-50 mg/day to reach effective dose 1
• Mean oral clearance is reduced by approximately 25% in patients with hepatic cirrhosis 3

Renal Impairment

• Mean oral clearance is reduced by approximately 25% in patients with severe renal impairment 3

Evidence on Higher Doses

While the FDA-approved maximum is 750-800 mg/day depending on indication, some clinical data exist on higher doses:

• One open-label study examined doses up to 1600 mg/day in hospitalized patients with various psychotic disorders, reporting that 83.3% of patients receiving >800 mg/day were "very much" or "much improved" with no increase in extrapyramidal symptoms 4
• However, systematic review of fixed-dose efficacy studies indicates that dosages of 150-450 mg/day are as effective as 600-750 mg/day, with no robust controlled data supporting routine use above 800 mg/day 5

The balance of evidence does not support exceeding the FDA-approved maximum doses in routine clinical practice. 5

Critical Safety Monitoring

Cardiovascular

• Monitor for orthostatic hypotension, especially during initial dose titration 2, 6
• QTc prolongation can occur but quetiapine has less effect than other antipsychotics 2

Common Adverse Events

• Headache (19.4%), somnolence (17.5%), and dizziness (9.6%) are most common 3
• Weight gain averages approximately 2.1 kg in short-term trials 3

Metabolic Effects

• Small dose-related decreases in total and free thyroxine occur, usually reversing with treatment cessation 3
• Asymptomatic, transient elevations in hepatic transaminases may occur 3

Drug Interactions

• Avoid combining with high-dose olanzapine and benzodiazepines due to risk of oversedation and respiratory depression 2
• Pharmacokinetic interactions occur with CYP3A4 inducers or inhibitors, as quetiapine is extensively metabolized via this pathway 3

Important Caveats

• Never discontinue abruptly, as rapid dose decrease can produce withdrawal symptoms 2
• Quetiapine does not elevate plasma prolactin levels and has placebo-level incidence of extrapyramidal symptoms across its entire dose range 3, 7
• The half-life is approximately 6 hours, supporting twice-daily dosing for most indications 3