Would 37.5 mg of quetiapine (Seroquel) at bedtime be a suitable alternative to 50 mg for managing sleep and minimizing adverse effects such as excessive sedation and orthostatic hypotension?

Quetiapine Dosing for Sleep Management

Yes, reducing the dose to 37.5 mg of quetiapine at bedtime would be better than 50 mg to minimize adverse effects like excessive sedation and orthostatic hypotension while still providing sleep benefits. 1

Rationale for Lower Dose

Quetiapine is commonly used off-label for sleep management, though this practice requires careful consideration of benefits versus risks. The rationale for using a lower dose includes:

• Lower doses minimize risk of adverse effects while potentially maintaining efficacy for sleep
• The FDA recommends using "the smallest dose and shortest duration of treatment producing a satisfactory clinical response" 2
• Orthostatic hypotension is a significant concern with quetiapine, particularly during initial dose-titration periods 2

Dose-Related Adverse Effects

Quetiapine has several dose-dependent adverse effects that can be minimized with lower dosing:

• Orthostatic hypotension: Occurs in approximately 4% of patients and can lead to falls 2
• Excessive sedation: Reported in up to 18% of patients and can persist into the following day 2
• Falls risk: Atypical antipsychotics increase fall risk due to postural hypotension and sedation 2
• Cognitive effects: Higher doses may contribute to next-day cognitive impairment, especially in older adults 3

Evidence Supporting Lower Dosing

Recent evidence suggests particular caution with quetiapine dosing:

• A 2025 study showed significantly higher rates of mortality, dementia, and falls in older adults using low-dose quetiapine for insomnia compared to alternatives like trazodone 3
• Case reports document bradycardia and hypotension in elderly patients taking quetiapine, with improvement after dose reduction 4
• Even at low doses (25-200 mg/day), quetiapine has been associated with weight gain and potential metabolic effects 5

Alternative Options to Consider

If sleep disturbances persist despite dose adjustment, consider these alternatives recommended by guidelines:

• Trazodone: 25-100 mg at bedtime (preferred over quetiapine for insomnia) 6
• Mirtazapine: 7.5-30 mg at bedtime (especially effective if depression/anorexia are present) 6
• Zolpidem: 5 mg at bedtime (FDA recommended lower dose) 6

Implementation Approach

1. Start with 37.5 mg: Begin with this lower dose at bedtime
2. Monitor for effectiveness: Assess sleep quality and duration
3. Watch for side effects: Particularly morning sedation, dizziness, and orthostatic symptoms
4. Consider further reduction: If side effects persist, consider further reducing to 25 mg
5. Regular reassessment: Evaluate continued need for medication periodically

Special Considerations

• Elderly patients are at higher risk for adverse effects and should generally start at even lower doses (25 mg) 1
• Patients with cardiovascular disease require extra caution due to increased risk of orthostatic hypotension 2
• Risk of falls should be assessed regularly, especially in older adults 2

By reducing the dose to 37.5 mg at bedtime, you can potentially maintain sleep benefits while reducing the risk of troublesome side effects like excessive sedation and orthostatic hypotension.