A method for reducing the severity of heartburn and/or the risk of the occurrence of heartburn in a human in need of taking naproxen sodium for the treatment of acute pain wherein the human is not experiencing heartburn prior to the oral administration of the unit oral dose composition comprising orally administering to the human of a unit oral dose composition comprising (i) naproxen sodium at a dosage from about 100 mg to about 440 mg per unit oral dose composition and (ii) famotidine at a dosage from about 3 mg to about 20 mg per unit oral dose composition,
- wherein the dissolution rate of famotidine in the unit oral dose composition in said human at a specified time within 45 minutes of administration of said unit oral dose composition to said human is greater than the dissolution rate of naproxen sodium in the unit oral dose composition in said human at the same specified time.