Introduction and method: The mechanism of action of interferons We do not know in the multiple sclerosis but, although exist discrepancies in relation to their degree of effectiveness, fundamentally the dose to use and the administration route, the three available ones have proven to be effective in the reduction of the number of the bouts. We reviewed the more important clinical tests made with three interferons in the remitent recurrent (RR) forms, the isolated neurologic syndromes and the secondary progressive (SP) forms of the disease and reviewed the comparative studies between interferons.
Conclusions: The three interferons are well tolerated although the intramuscular form produces less skin effects; in the RR forms the number of bouts are reduced in significant form. Only the study with 1a intramuscular was demonstrated effectiveness in the SP forms and with the subcutaneous IFN b 1b exists discrepancies between the European and the American studies. The early treatment with subcutaneous IFN b 1a slow down the evolution of the disease. Except in relation to the side effects, there are not evidence that the dose and the administration route are important in the effectiveness in the long term.