Do not use if you are allergic to cimetidine or other acid reducers. 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. Ask a doctor before use if you have: frequent chest pain, frequent wheezing, particularly with heartburn, unexplained weight loss, nausea or vomiting, stomach pain, 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. Ask a doctor or pharmacist before use if you are taking: theophylline (oral asthma medicine), warfarin (blood thinning medicine), phenytoin (seizure medicine) (if you are not sure you are taking one of these medicines, talk to your doctor or pharmacist). Stop use and ask a doctor if: your heartburn continues or worsens, stomach pain continues, you need to take this product for more than 14 days. If pregnant or breastfeeding, 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. Each tablet individually sealed in a blister pack. Do not use if blister or foil is open or torn.