Rugby Laboratories Antacid Liquid Regular Strength Aluminum Hydroxide 400 mg Magnesium Hydroxide 400 mg Simethicone 40 mg, Original Flavor. PURPOSE: Antacid, Antigas. Relieves acid indigestion, heartburn, sour stomach, upset stomach and gas associated with these symptoms. Shake well. Take 2 to 4 teaspoonfuls between meals, at bedtime or as directed by a doctor. NDC Code(s): 0536-1293-83