Major collapse requires full resuscitation. Convulsions may occur and need management of airway, breathing and circulation as well as control of the fitting with diazepam or thiopentone. These are the main analgesic treatment for mild to moderate pain. Aspirin is an effective analgesic and is widely available throughout the world. It is active orally within a short period as it is rapidly metabolised into salicylic acid which has analgesic and, probably, anti-inflammatory activity.
Salicylic acid has a half life of about four hours at therapeutic doses.
Excretion is dose dependent and high doses will be excreted more slowly. The length of action may be reduced if aspirin is given with antacids. Aspirin has major gastrointestinal side effects and may cause nausea, sickness or gastrointestinal bleeding because of antiplatelet effects which are irreversible. For this latter reason the use of aspirin after surgery should be withheld if alternatives are available. Diflunisal and Choline salicylate are related compounds without this latter problem.