ACTIVE INGREDIENT: The active ingredient in these delayed release tablets is omeprazole 20 mg, which works as an acid reducer to treat frequent heartburn. Compare to Prilosec OTC TREATS FREQUENT HEARTBURN: Walgreens Omeprazole Delayed Release Tablets 20 mg treat frequent heartburn that occurs 2 or more times a week ACID REDUCER: Well at Walgreens Omeprazole Delayed Release Tablets 20 mg is a Proton Pump Inhibitor (PPI) that deactivates pumps in the stomach lining to inhibit acid production at the source. 14-DAY COURSE OF HEARTBURN TREATMENT: Taken once every 24 hours for 14 days, Walgreens Omeprazole Delayed Release Tablets 20 mg is not intended for immediate relief of heartburn and may take 1 to 4 days for full effect. HEARTBURN TIPS: Do not eat late at night or just before bedtime. Certain foods or drinks are more likely to cause heartburn, such as rich, spicy, fatty and fried foods, chocolate, caffeine, alcohol and even some fruits and vegetables.