Drug interactions
Phenobarbital + Thioridazine
Severity: Moderate
Phenobarbital and Thioridazine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Both drugs cause central nervous system depression, so combined use increases sedation and may impair alertness and respiration. Phenobarbital also induces hepatic enzymes and may lower thioridazine concentrations, and thioridazine may lower the seizure threshold.
What this interaction means in plain words
Phenobarbital and Thioridazine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Additive central nervous system depression plus phenobarbital enzyme induction.
What to do
Monitor sedation and, in epilepsy, seizure control. Adjust doses according to clinical response.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Thioridazine
- Abiraterone + Thioridazine Contraindicated
- Adagrasib + Thioridazine Contraindicated
- Amiodarone + Thioridazine Contraindicated
- Amisulpride + Thioridazine Contraindicated
- Amitriptyline + Thioridazine Contraindicated
- Amoxapine + Thioridazine Contraindicated
Frequently asked questions
Can I take Phenobarbital with Thioridazine?
MediHelp rates the interaction as moderate. Phenobarbital and Thioridazine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Both drugs cause central nervous system depression, so combined use increases sedation and may impair alertness and respiration. Phenobarbital also induces hepatic enzymes and may lower thioridazine concentrations, and thioridazine may lower the seizure threshold.
How serious is the interaction between Phenobarbital and Thioridazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor sedation and, in epilepsy, seizure control. Adjust doses according to clinical response.
What other medicines interact with Thioridazine?
MediHelp also lists interactions of Thioridazine with, for example, Abiraterone, Adagrasib, Amiodarone. The full list is on the Thioridazine page.
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