 [ Symptoms ] my 2 week old is sleeping about 6 7 hours a night i am breastfeeding and was told to wake her every 3 hours should i [ Disease ] no a regular multivitamin will not affect the absorption of birth control pills there are no drug interactions you should always check with your pharmacist before taking over the counter medications vitamins or supplements when you use a prescription medication your pharmacist would be the best person to help you avoid drug interactions