Do caffeine-containing analgesics promote dependence? A review and evaluation

Objective: Debates about the suspected association between kidney disease a nd use of analgesics have led to concern about whether caffeine could stimu late an undesirable overuse of phenacetin-free combined analgesics. A commi ttee was asked to critically review the pertinent literature and to suggest guides for clinical practice and for consideration of international regula tory authorities. Participants: A group of international scientists, jointly selected by the regulatory authorities of Germany, Switzerland, and Austria and the pharmac eutical industry. Evidence: All invited experts evaluated relevant literature and reports and added further information and comments. Conclusions Caffeine has a synergistic effectiveness with analgesics. Altho ugh caffeine has a dependence potential, the potential is low. Experimental data regarding dependence potential for caffeine alone may not correspond to the conditions in patients with pain. Withdrawal is not likely to cause stimulation or sustainment of analgesic intake. For drug-induced headache, no single or combined analgesic was consistently identified as causative, a nd no evidence exists for a special role of caffeine. Strong dependence beh avior was observed only in patients using phenacetin-containing preparation s, coformulated with antipyretics/analgesics and caffeine. This finding may have led to the impression that caffeine stimulates overuse of analgesics, Summary: Although more experimental and long-term data would be desirable t o show possible mechanisms of dependence and to offer unequivocal proof of safety, the committee concluded that the available evidence does not suppor t the claim that analgesics coformulated with caffeine, in the absence of p henacetin, stimulate or sustain overuse.