PRECAUTIONS: Before taking penicillin, tell your doctor or pharmacist if you are allergic to it; or to other antibiotics including penicillin-type medications (e.g., amoxicillin, ampicillin) or cephalosporins (e.g., cephalexin, cefuroxime); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney problems.This medication may contain aspartame. If you have phenylketonuria (PKU) or any other condition that requires you to restrict your intake of aspartame (or phenylalanine), consult your doctor or pharmacist regarding the safe use of this medicine.Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be more sensitive to this drug.Kidney function is not fully developed in newborns and young infants. This medication is removed by the kidneys. Therefore, newborns and young infants may be more sensitive to this drug.This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.This drug passes into breast milk. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Your healthcare professionals (e.g., doctor or pharmacist) may already be aware of any possible drug interactions and may be monitoring you for it. Do not start, stop or change the dosage of any medicine before checking with them first.Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: live bacterial vaccines, methotrexate, tetracyclines, khat, guar gum.Before taking penicillin, tell your doctor or pharmacist if you are also taking probenecid. Probenecid slows down the removal of penicillin from your body, resulting in higher levels of this antibiotic in your bloodstream. For certain types of difficult-to-treat infections, your doctor may prescribe these 2 medications together in order to achieve this effect. Consult your doctor or pharmacist for more details.Although most antibiotics probably do not affect hormonal birth control such as pills, patch, or ring, some antibiotics may decrease their effectiveness. This could cause pregnancy. Examples include rifamycins such as rifampin or rifabutin. Be sure to ask your doctor or pharmacist if you should use additional reliable birth control methods while using this antibiotic.Penicillin may cause false positive results with certain diabetic urine testing products (cupric sulfate-type). This drug may also affect the results of certain lab tests. Make sure laboratory personnel and your doctors know you use this drug.This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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