Do certain foods have the potential to interact with over-the-counter medications?
A. Yes, certain foods and beverages can interact with medicines – potentially making them less effective or causing side effects. Changes in a medicines effect due to an interaction can be significant, however, there are many individual factors that influence the potential for variations, such as dosage, age, weight, sex and overall health. Calcium-rich dairy products (such as milk, cheese and ice cream), antacids and vitamins containing iron can all lessen the effectiveness of antibiotics, particularly tetracycline. Mixing any of these with a prescription antibiotic can cause a much slower absorption rate of the antibiotic into the blood stream/body, causing it to have a decreased effect. Grapefruit juice blocks enzymes that normally metabolize certain drugs, leaving more of the compounds to be absorbed and thus increasing blood levels of the medications. For example, grapefruit juice should not be taken with certain blood pressure-lowering medications, the antihistamine terfenadine a
