Milk of Magnesia Oral belongs to the class of Osmotic Laxatives. This over-the-counter medicine is used for the treatment of acid reflux, constipation, heart burn, indigestion, flatulence, hyperacidity, sour stomach and stomach discomfort. The side effects of Milk of Magnesia Oral include - Stomach ache - Nausea and vomiting - Diarrhea - Muscle weakness - Hypotension - Electrolyte imbalance - Respiratory distress - Chalky taste - Light headedness Milk of Magnesia Oral interacts with the following drugs. - Tetracycline - Ketoconazole - Digoxin - Penicillamine - Biphosphonates