"Detailed brain scans (magnetic resonance images or MRI) every four weeks were used to check for new areas of neurological inflammation, a hallmark of active disease. In total, 38 patients--19 in each group--completed the study. The scans showed that those in the placebo group had more new areas of inflammation than those treated with Prozac.
The effects began to become evident after eight weeks, which corresponds to the time the selective serotonin reuptake inhibitor (SSRI) class of drugs, of which Prozac is one, start to work on relieving depression.
The average number of new areas affected was more than five in the group given the placebo compared with just under two in the group given Prozac. One in four scans from patients treated with Prozac showed new areas of inflammation compared with four out of 10 of those taking placebo.
During the last 16 weeks of treatment, almost two thirds of patients (63%) in the group given Prozac had no new areas of inflammation compared with only one in four (26%) in the group given placebo.
The authors caution that their study was small, and larger studies would be needed before firm conclusions could be drawn."