Based on the study abstract from Pubmed below, I say if you hate it, stop right now!
MRI and clinical activity in MS patients after terminating treatment with interferon beta-1b.
Mult Scler. 2000 Apr;6(2):86-90.
Richert ND, Zierak MC, Bash CN, Lewis BK, McFarland HF, Frank JA.
Laboratory of Diagnostic Radiology Research, Clinical Center, NIH, Bethesda, Maryland, MD 20892, USA.
Monthly MRI activity and clinical disability were evaluated in two relapsing-remitting multiple sclerosis (RRMS) patients for 4 years during a cross-over treatment trial with IFNbeta-1b, and for a mean of 21 months after terminating treatment with IFNbeta-1b. Post-treatment MRI activity was compared to baseline activity in these patients. Although contrast enhancing lesions (CEL) and the bulk white matter lesion load (BWMLL) on T2-weighted images eventually returned to baseline values, there was a refractory period of 6 - 10 months after terminating treatment, before baseline MRI activity was restored. Although the mechanism for a sustained effect of IFNbeta-1b is unclear at this time, these results have important implications for enrollment of such patients into new treatment protocols that rely on contrast enhancing lesion frequency as an outcome measure.