Standard Adult Dosages for Common Uses
Aspirin dosages vary by purpose. For pain relief, fever, or headaches, adults typically take 325-650 mg every 4-6 hours, not exceeding 4 grams daily. Low-dose aspirin for heart attack or stroke prevention is usually 81 mg (often called "baby aspirin") once daily.[1][2]
Dosages for Children
Children under 16 rarely get aspirin due to Reye's syndrome risk. When used (e.g., for Kawasaki disease under medical supervision), it's 80-100 mg/kg/day divided into doses.[3]
Heart Health and Prevention Specifics
For primary prevention of cardiovascular events, guidelines recommend 75-162 mg daily for at-risk adults, but recent trials question routine use due to bleeding risks. Secondary prevention (post-heart attack) sticks to 75-325 mg daily.[4]
What If You Miss a Dose?
Take it as soon as remembered unless near the next dose; don't double up to avoid overdose risks like stomach bleeding.[2]
Overdose Risks and Maximum Limits
Exceeding 4 grams daily can cause tinnitus, nausea, or severe bleeding. Seek emergency care for suspected overdose.[1]
Factors Affecting Dosage
Age, weight, liver/kidney function, and other drugs (e.g., blood thinners) adjust doses. Always consult a doctor; self-dosing enteric-coated versions doesn't reduce GI risks.[3]
[1]: FDA Aspirin Label
[2]: Mayo Clinic Aspirin Dosing
[3]: Medscape Aspirin Dosing
[4]: USPSTF Aspirin Recommendations