Formulations of Aspirin

A wide range of preparations of aspirin are available, both alone and in combination with other drugs. Aspirin is also remarkably widely distributed - more widely perhaps than any other drug. It was taken to the Antarctic by Scott, up Everest by Hillary and to the moon by astronauts!

Soluble preparations are very rapidly absorbed and within five minutes can achieve relatively high plasma levels. (46) Occult blood loss is about half as much with soluble formulations as with standard aspirin. (51)

Mouth-dispersible tablets have the advantage that they are easily taken without water. Peak plasma levels occur somewhat sooner than with conventional aspirin. (46)

Modified release tablets are coated with polymer and release aspirin over a period of hours. There are concerns over the erratic absorption of aspirin from enteric-coated tablets used in low doses (53).

Evidence of a possible protective effect against major gastrointestinal bleeding at low doses is conflicting (52a) (52b).