Whether taking half an aspirin a day is effective or not cannot be generalized. It has to be viewed in the light of the aspirin’s dosage form, the dose and the purpose of the treatment. The dosage forms of aspirin are tablets, effervescent tablets, enteric-coated tablets, granules and suppositories, etc. The dosage is different for different dosage forms, for example, aspirin tablets and effervescent tablets are 0.3g or 0.5g, enteric-coated tablets are 25mg, 40mg, 50mg, 0.1g and 0.3g. Generally speaking, for antipyretic and analgesic generally take 0.3-0.6g can be, pediatric need to halve the dose, in this case half a tablet of aspirin a day is effective, can play a fever, analgesic effect. But for the inhibition of platelet aggregation, prevention of myocardial infarction, arterial thrombosis, atherosclerosis, it is recommended that each time 75-150mg, once a day, because of the need for long-term use, in order to reduce the stimulation of the gastrointestinal tract, it is recommended that the use of aspirin enteric-coated tablets, but enteric-coated tablets are not recommended to be broken open for use. Therefore, taking aspirin need to follow the doctor’s advice to choose the right form and dose, do not change the drug form and dose without authorization, to avoid the drug is not the right medicine, damage to the body, and delay the disease.