ROLAIDS ULTRA STRENGTH 1200 (CALCIUM CARBONATE, MAGNESIUM HYDROXIDE) TABLET, CHEWABLE [THE PROCTER & GAMBLE MANUFACTURING COMPANY] now taking a prescription drug. Antacids may interact with certain prescription drugs. do not take more than 7 tablets in a 24-hour period do not use the maximum dosage for more than 2 weeks, except under the advice and supervision of a doctor