Does red grapefruit affect my drugs?

Hello,
This will depend on which medicine(s) you are talking about.
Most benzodiazepine(s) are affected because grapefruits hinder the way your body reactive (absorb) them. Could make the medicine stronger or weaker or nothing at all. If you're on this medicine long term already than it probably won't change.

A more precise list of your meds would be necessary.

Best regards
Kevinb1953

What meds are you on?