Alprazolam × Quetiapine

Both drugs depress the central nervous system. The alprazolam SmPC warns that with antipsychotics the depressant effect can increase, up to respiratory depression, coma and death. Quetiapine acts mainly on the central nervous system, so its SmPC asks for caution when it is combined with other centrally acting drugs.

Drowsiness, sedation, slowed reactions, poor coordination. Quetiapine can cause a drop in blood pressure on standing with dizziness, mostly at the start of treatment and during dose titration, and together with sedation this raises the risk of falls, above all in older people (quetiapine and alprazolam SmPCs). Marked central nervous system depression can lead to slowed breathing and coma (alprazolam SmPC). Driving and operating machinery become riskier.

The combination is not prohibited, but the alprazolam SmPC requires limiting the dose and duration of its use with antipsychotics, and quetiapine is one of them. The US Food and Drug Administration (FDA) alprazolam label requires the same with any central nervous system depressant, and the quetiapine SmPC asks for caution with other centrally acting drugs. Alprazolam is given for as short a time as possible, no longer than 2–4 weeks without reassessment; older or debilitated patients start at a lower dose, the dose is reduced in chronic respiratory insufficiency, and alprazolam is contraindicated in severe respiratory insufficiency and sleep apnoea syndrome (alprazolam SmPC). Warn the patient about drowsiness and dizziness on standing, especially at the start of quetiapine treatment and during dose titration (quetiapine SmPC).