Refers to drug mixtures that include aspirin as one of the components. Commonly other analgesics (e.g., acetaminophen, codeine, propoxyphene), stimulants (usually caffeine), or both are combined with aspirin. Aspirin may be combined with other drugs. Because many of these preparations can be obtained without a doctor's prescription, individuals may develop a regular self-medication habit and are at risk of developing gastrointestinal symptoms (e.g., peptic ulcer) and other toxic reactions if these combinations are over-used.