how many mg of aspirin can i take
However, general guidelines are as follows: 1  For a headache or muscle ache, take 325 mg of aspirin every 4-6 hours. 2  To prevent a heart attack, take two low-dose (81 mg) aspirin every day if youâre at risk or over 40. If you think youâre having a heart attack, take 325 mg of aspirin, and make sure to chew the aspirin before swallowing, because it gets into the bloodstream quicker.