I know of no contrainidication to photofacials and IPL in patients with Multiple Sclerosis. It is always recommended that you discuss this with your internist or neurologist, however, before proceding and to discuss it with you laser physican (yes a doctor and not a technician). The laser...
General rule of thumb: if it's strong enough to cause a permanent change, it needs to be performed by a certified professional under the supervision of a board certified plastic surgeon.
All devices have a long list of precautions and I cannot recommend you to do something against the product label. IPLs do not penetrate very deep and home machines are even less. They are worried about you increasing blood flow to the area of your thyroid if you treat over the mid neck....