fiber and medications

Fiber can reduce medication absorption

What's happening

Fiber supplements can bind to medications and reduce their absorption. Affects many medications.

Recommendation

Take medications 1-2 hours before or after fiber supplements.

Timing

Separate by 1-2 hours

Sources

— American Journal of Health-System Pharmacy

Frequently Asked Questions

Can I take fiber and medications together?

Fiber can reduce medication absorption. Take medications 1-2 hours before or after fiber supplements.

How should I time fiber and medications?

Separate by 1-2 hours

Is this interaction dangerous?

This interaction is rated “Caution” by Formulate. Fiber supplements can bind to medications and reduce their absorption. Affects many medications.

Cited research

Studies from our registry that mention fiber or medications. Each links to the primary source and the other Formulate pages citing it.

Mentions fiber · 2005
Acetyl-L-carnitine for the treatment of diabetic peripheral neuropathy: a long-term, randomised, double-blind, placebo-controlled study
Sima AA, Calvani M, Mehra M, Amato A · Diabetes Care
52-week RCT (n=1,257) found ALCAR 1000mg three times daily improved vibration perception, sural nerve fiber regeneration, and pain scores in diabetic peripheral neuropathy.

More interactions involving fiber or medications

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Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.

Last medically reviewed: April 21, 2026