Chronic overdose is more commonly lethal, with a mortality rate of 25%; chronic overdose may be especially severe in children. Toxicity is managed with a number of potential treatments, including activated charcoal, intravenous dextrose and normal saline, sodium bicarbonate, and dialysis. The diagnosis of poisoning usually involves measurement of plasma salicylate, the active metabolite of aspirin, by automated spectrophotometric methods. Plasma salicylate levels in general range from 30 to 100 mg/L after usual therapeutic doses, 50–300 mg/L in people taking high doses and 700–1400 mg/L following acute overdose. Salicylate is also produced as a result of exposure to bismuth subsalicylate, methyl salicylate, and sodium salicylate. Interactions
Aspirin is known to interact with other drugs. For example, acetazolamide and ammonium chloride are known to enhance the intoxicating effect of salicylates, and alcohol also increases the gastrointestinal bleeding associated with these types of drugs. Aspirin is known to displace a number of drugs from protein-binding sites in the blood, including the antidiabetic drugs tolbutamide and chlorpropamide, warfarin, methotrexate, phenytoin, probenecid, valproic acid (as well as interfering with beta oxidation, an important part of valproate metabolism), and other NSAIDs. Corticosteroids may also reduce the concentration of aspirin. Other NSAIDs, such as ibuprofen and naproxen, may reduce the antiplatelet effect of aspirin. Although limited evidence suggests this may not result in a reduced cardioprotective effect of aspirin. Analgesic doses of aspirin decrease sodium loss induced by spironolactone in the urine, however this does not reduce the antihypertensive effects of spironolactone.
: 8–13  Hippocrates referred to the use of salicylic tea to reduce fevers around 400 BC, and willow bark preparations were part of the pharmacopoeia of Western medicine in classical antiquity and the Middle Ages. Willow bark extract became recognized for its specific effects on fever, pain, and inflammation in the mid-eighteenth century. By the nineteenth century, pharmacists were experimenting with and prescribing a variety of chemicals related to salicylic acid, the active component of willow extract. : 46–55 

In 1853, chemist Charles Frédéric Gerhardt treated sodium salicylate with acetyl chloride to produce acetylsalicylic acid for the first time;: 46–48  in the second half of the 19th century, other academic chemists established the compounds chemical structure and devised more efficient methods of synthesis. In 1897, scientists at the drug and dye firm Bayer began investigating acetylsalicylic acid as a less-irritating replacement for standard common salicylate medicines, and identified a new way to synthesize it. : 69–75  By 1899, Bayer had dubbed this drug Aspirin and was selling it globally. : 27  The word Aspirin was Bayers brand name, rather than the generic name of the drug; however, Bayers rights to the trademark were lost or sold in many countries. Aspirins popularity grew over the first half of the 20th century leading to fierce competition with the proliferation of aspirin brands and products.Aspirins popularity declined after the development of acetaminophen/paracetamol in 1956 and ibuprofen in 1962.