With one Prilosec OTC pill a day, you can block frequent heartburn symptoms before they strike for a full 24 hours of heartburn relief. That way you can power on with your day – and rest at night – without concern that your frequent heartburn will flare up. That’s because Prilosec OTC fights heartburn day and night by shutting down many of the acid pumps in your stomach. It can be the all-day, all-night heartburn protection you need.