SIDE EFFECTS: This medication can cause nausea, constipation, diarrhea, or headache. If these symptoms persist or become severe, notify your doctor. If your doctor has directed you to use this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. The magnesium in this product can cause diarrhea. Using an antacid that contains only aluminum along with this product can help control diarrhea. The aluminum in this product can cause constipation. To minimize constipation, drink plenty of fluids and exercise. Diarrhea is more common with this product than constipation. Aluminum-containing antacids bind to phosphate, an important body chemical, in the gut. This can cause low phosphate levels, especially if you use this medication in large doses and for a long time. Tell your doctor right away if you have any of the following symptoms of low phosphate: loss of appetite, unusual tiredness, muscle weakness. Tell your doctor right away if any of these unlikely but serious side effects occur: dizziness, fainting. Seek immediate medical attention if any of these rare but very serious side effects or symptoms of a serious medical problem occur: black/tarry stools, slow/shallow breathing, slow/irregular heartbeat, mental/mood changes (e.g., confusion), deep sleep, pain with urination, stomach/abdominal pain, vomit that looks like coffee grounds. A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking this product, tell your doctor or pharmacist if you are allergic to aluminum hydroxide; or to magnesium; 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. If you have any of the following health problems, consult your doctor or pharmacist before using this product: frequent alcohol use, severe loss of body water (dehydration/fluid restriction), kidney problems (including kidney stones). This medicine 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 about using this drug safely. During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. This medication may pass into breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: See also How to Use section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: phosphate supplements (such as potassium phosphate), sodium polystyrene sulfonate. Antacids can interfere with the absorption of many other drugs. Be sure to check with your pharmacist before taking antacids with any other medication.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.