For headache pain, the recommended adult dose of aspirin is 325 to 650 mg every three to four hours as needed, up to six times per day. While aspirin may help alleviate acute migraine pain, it shouldn't be used more than twice a week for this purpose since rebound — or medication overuse — headaches can occur.or headache pain, the recommended adult dose of aspirin is 325 to 650 mg every three to four hours as needed, up to six times per day. While aspirin may help alleviate acute migraine pain, it shouldn't be used more than twice a week for this purpose since rebound — or medication overuse — headaches can occur.