Allergy alert: Do not use if you are allergic to famotidine or other acid reducers. Ask a doctor before use if you have had heartburn over 3 months. This may be a sign of a more serious condition. heartburn with lightheadedness, sweating, or dizziness chest pain or shoulder pain with shortness of breath; sweating; pain spreading to arms, neck or shoulders; or lightheadedness frequent chest pain frequent wheezing, particularly with heartburn unexplained weight loss nausea or vomiting stomach pain. Ask a doctor or pharmacist before use if you are presently taking a prescription drug. Antacids may interact with certain prescription drugs. If pregnant or breast-feeding, ask a health professional before use. Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center right away (1-800-222-1222). Do not use if you have trouble or pain swallowing food, vomiting with blood, or bloody or black stools. These may be signs of a serious condition. See your doctor. with other acid reducers. Stop use and ask a doctor if your heartburn continues or worsens you need to take this product for more than 14 days.