What should I know about penicillin V potassium before taking it?

Before you take penicillin V potassium, also known as penicillin VK, tell your doctor if you have asthma, seizure or kidney disorders or any allergies, especially allergies to penicillin or tartrazine, a yellow dye sometimes used in foods and drugs. This medicine is taken orally. You should not use this drug if you have had an allergic reaction to cephalosporin antibiotics, without first letting your doctor know. It may not be recommended if you have symptoms such as nausea, vomiting or diarrhea, so consult your doctor. Penicillin V potassium is only effective in preventing or treating bacterial infections. It is not an effective treatment for viral infections. If you are pregnant or become pregnant while taking this medicine, or breastfeeding tell your doctor right away. Tell your doctor if you are taking any over-the-counter or prescription medications, especially anticoagulants, atenolol, antibiotics, aspirin, oral contraceptives, probenecid, vitamins or nonsteroidal anti-inflammatories (NSAIDS). This medication must be taken exactly as prescribed. Make sure to take the entire prescription, even if you are feeling better.