Drug interactions
Liothyronine + Phenobarbitone
Severity: Moderate
Liothyronine and Phenobarbitone: 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
Phenobarbital induces hepatic enzymes and can accelerate liothyronine clearance. This may lower thyroid hormone levels and cause hypothyroid symptoms.
What this interaction means in plain words
Liothyronine and Phenobarbitone 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.
Liothyronine belongs to Endocrine; Phenobarbitone belongs to Central Nervous System.
Why it happens
Hepatic enzyme induction increases thyroid hormone metabolism.
What to do
Monitor TSH and clinical status after starting or stopping phenobarbital. Increase the liothyronine dose if needed.
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 Liothyronine
- Alogliptin-metformin + Liothyronine Moderate
- Amitriptyline + Liothyronine Moderate
- Amobarbital + Liothyronine Moderate
- Canagliflozin-metformin + Liothyronine Moderate
- Carbamazepine + Liothyronine Moderate
- Carbonyl iron + Liothyronine Moderate
Other interactions of Phenobarbitone
- Cabotegravir + Phenobarbitone Contraindicated
- Doravirine + Phenobarbitone Contraindicated
- Isavuconazole + Phenobarbitone Contraindicated
- Darolutamide + Phenobarbitone Major
- Finerenone + Phenobarbitone Major
- Ivacaftor + Phenobarbitone Major
Frequently asked questions
Can I take Liothyronine with Phenobarbitone?
MediHelp rates the interaction as moderate. Liothyronine and Phenobarbitone 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. Phenobarbital induces hepatic enzymes and can accelerate liothyronine clearance. This may lower thyroid hormone levels and cause hypothyroid symptoms.
How serious is the interaction between Liothyronine and Phenobarbitone?
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 TSH and clinical status after starting or stopping phenobarbital. Increase the liothyronine dose if needed.
What other medicines interact with Liothyronine?
MediHelp also lists interactions of Liothyronine with, for example, Alogliptin-metformin, Amitriptyline, Amobarbital. The full list is on the Liothyronine page.
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