Prescription aspirin comes as an extended-release ( long-acting) tablet. Nonprescription aspirin comes as a regular tablet, a delayed-release (releases the medication in the intestine to prevent damage to the stomach) tablet, a chewable tablet, powder, and a gum to take by mouth and a suppository to use rectally. Prescription aspirin is usually taken two or more times a day. Nonprescription aspirin is usually taken once a day to lower the risk of a heart attack or stroke. Nonprescription aspirin is usually taken every 4 to 6 hours as needed to treat fever or pain. Follow the directions on the package or prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take aspirin exactly as directed. Do not take more or less of it or take it more often than directed by the package label or prescribed by your doctor.