Acetaminophen? Not sure what else.
This older paper describes several:
Non-NSAID pharmacologic treatment options for the management of chronic pain
Am J Med: 1998 Jul 27;105(1B):45S-52S
Excerpt:
" Several non-NSAID, non-narcotic therapies are available for noninflammatory pain.
Acetaminophen is as effective as NSAIDs for the management of mild-to-moderate OA pain and is the recommended first-line therapy by the American College of Rheumatology (ACR).
Propoxyphene, widely believed to be safe and effective, may, in fact, be no more effective-and perhaps less effective-than acetaminophen or ibuprofen. A relatively new analgesic,
tramadol, appears to be a useful therapy for patients who do not receive adequate pain relief with acetaminophen and are at risk for NSAID-related side effects. For localized chronic pain associated with OA, topical capsaicin is also an effective analgesic."