Does taking a multi-vitamin affect birth control effectiveness?
No, multi-vitamins do not affect the effectiveness of oral contraceptives. However, drug interactions with oral contraceptives are of two types; effects of other drugs on oral contraceptive efficacy and the effects of oral contraceptives on other drugs.
Oral contraceptives do affect serum plasma or blood levels of vitamin and minerals in your body. They may increase Vitamin A, copper and iron. They may decrease thiamine (B1), riboflavin (B2), pyridoxine (B6), cobalamin (B12), ascorbic acid (C), folic acid, calcium, magnesium, and zinc.
Because of these effects it is important to take a multi-vitamin and calcium with magnesium and Vitamin D3 while you are taking oral contraceptives.
Remember, it is important to let your health care provider know of any prescription, over the counter or herbal supplements that you may be taking.
Please contact your health care provider if you have any other questions.