Drug interactions
Cholestyramine + Simvastatin
Severity: Moderate
Cholestyramine and Simvastatin: 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
Cholestyramine is a bile acid sequestrant that can bind simvastatin in the gut and lower its absorption if taken at the same time. This may reduce the cholesterol-lowering effect of simvastatin, although the combination is often used deliberately for additive lipid lowering.
What this interaction means in plain words
Cholestyramine and Simvastatin 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.
Cholestyramine belongs to Cardiovascular; Simvastatin belongs to Cardiovascular.
Why it happens
Cholestyramine binds simvastatin in the gastrointestinal tract, reducing its absorption.
What to do
Give simvastatin at least 2 hours before or 4 hours after cholestyramine. Monitor the lipid profile.
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 Simvastatin
- Atazanavir + Simvastatin Contraindicated
- Clarithromycin + Simvastatin Contraindicated
- Cobicistat + Simvastatin Contraindicated
- Cyclosporin + Simvastatin Contraindicated
- Danazol + Simvastatin Contraindicated
- Darunavir + Simvastatin Contraindicated
Other interactions of Cholestyramine
Frequently asked questions
Can I take Cholestyramine with Simvastatin?
MediHelp rates the interaction as moderate. Cholestyramine and Simvastatin 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. Cholestyramine is a bile acid sequestrant that can bind simvastatin in the gut and lower its absorption if taken at the same time. This may reduce the cholesterol-lowering effect of simvastatin, although the combination is often used deliberately for additive lipid lowering.
How serious is the interaction between Cholestyramine and Simvastatin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Give simvastatin at least 2 hours before or 4 hours after cholestyramine. Monitor the lipid profile.
What other medicines interact with Simvastatin?
MediHelp also lists interactions of Simvastatin with, for example, Atazanavir, Clarithromycin, Cobicistat. The full list is on the Simvastatin page.
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