Aspirin

Therapeutic uses

Aspirin is one of the most frequently used drugs in the treatment of mild to moderate pain, including that of migraines, and fever. It is often combined with other analgesics, even though this has never been shown to be more effective or less toxic than aspirin alone. Aspirin has, however, been used in addition to other non-steroidal anti-inflammatory drugs and opioid analgesics in the treatment of pain associated with cancer.

In high doses, aspirin and other salicylates are used in the treatment of rheumatic fever, rheumatic arthritis, and other inflammatory joint conditions. In lower doses, aspirin also has properties as an inhibitor of platelet aggregation, and has been shown to decrease the incidence of transient ischemic attacks and unstable angina in men, and can be used prophylactically. It is also used in the treatment of pericarditis, coronary artery disease, and acute myocardial infarction.Low doses of aspirin are also recommended for the prevention of stroke, and myocardial infarction in patients with either diagnosed coronary artery disease or who have an elevated risk of cardiovascular disease. It is also possible that women may benefit less from aspirin than men.

Dosage

For adults doses of 300 to 1000 mg are generally taken four times a day for fever or arthritis, with a maximum dose of 8000 mg (8 grams) a day.The correct dose of aspirin depends on the disease or condition that is being treated. For instance, for the treatment of rheumatic fever, doses near the maximal daily dose have been used historically.For the prevention of myocardial infarction in someone with documented or suspected coronary artery disease, doses as low as 75 mg daily (or possibly even lower) are sufficient.

For those under 12 years of age, the dose previously varied with the age, but aspirin is no longer routinely used in children due to the association with Reye's syndrome; paracetamol  or other NSAIDs , such as ibuprofen, are now used instead. Kawasaki disease remains one of the few indications for aspirin use in children, with aspirin initially started at 7.5–12.5 mg per kilogram of body weight, taken four times a day for up to two weeks and then continued at 5 mg/kg once daily for a further six to eight weeks.

Overdose

Aspirin overdose can be acute or chronic. In acute poisoning, a single large dose is taken; in chronic poisoning, supratherapeutic doses are taken over a period of time. Acute overdose has a mortality rate of 2%. Chronic overdose is more commonly lethal with a mortality rate of 25%; chronic overdose may be especially severe in children.

Symptoms

Aspirin overdose has potentially serious consequences, sometimes leading to significant morbidity and mortality. Patients with mild intoxication frequently have nausea and vomiting, abdominal pain, lethargy, tinnitus, and dizziness. More significant symptoms occur in more severe poisonings and include hyperthermia, tachypnea, respiratory alkalosis, metabolic acidosis, hyperkalemia, hypoglycemia, hallucinations, confusion, seizure, cerebral edema, and coma. The most common cause of death following an aspirin overdose is cardiopulmonary arrest usually due to pulmonary edema.