Disclosed are compositions comprising non-steroid anti-inflammatory drugs (NSAID'S) complexed with zwitterionic, neutral phospholipids, or both, having reduced gastrointestinal irritating effects and enhanced antipyretic, analgesic, and antiinflammatory activity. Also disclosed are improved methods of using the complexes for treating fever, inflammation, and preventing platelet aggregation. In some embodiments, the anti-pyretic activity of sub-therapeutically used amounts of NSAID's are enhanced to elicit anti-pyretic activity in vivo when associated (noncovalently) with zwitterionic phospholipids, such as dipalmitoyl phosphatidyl choline. Methods and compositions useful for enhancing the therapeutic activity of non-steroidal anti-inflammatory agents in the presence of anti-secretory agents are also discussed.