Drug interactions
Liraglutide + Promethazine
Severity: Minor
Liraglutide and Promethazine: minor 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
Phenothiazines such as promethazine can alter glucose control, and in some patients cause hyperglycemia, which may counteract the glucose-lowering effect of liraglutide. Promethazine is also sometimes used for nausea caused by liraglutide, so the combination is common in practice.
What this interaction means in plain words
Liraglutide and Promethazine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Liraglutide belongs to Endocrine; Promethazine belongs to Respiratory.
Why it happens
Pharmacodynamic opposition: phenothiazines can impair glucose tolerance, while liraglutide enhances glucose-dependent insulin secretion.
What to do
Monitor blood glucose when promethazine is started or stopped in patients on liraglutide, and adjust antidiabetic therapy if control changes.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Promethazine
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
- Amiodarone + Promethazine Major
- Amisulpride + Promethazine Major
Other interactions of Liraglutide
Frequently asked questions
Can I take Liraglutide with Promethazine?
MediHelp rates the interaction as minor. Liraglutide and Promethazine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Phenothiazines such as promethazine can alter glucose control, and in some patients cause hyperglycemia, which may counteract the glucose-lowering effect of liraglutide. Promethazine is also sometimes used for nausea caused by liraglutide, so the combination is common in practice.
How serious is the interaction between Liraglutide and Promethazine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood glucose when promethazine is started or stopped in patients on liraglutide, and adjust antidiabetic therapy if control changes.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Promethazine page.
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