I had this terribly and suddenly...with my lisinopril reaction. That is a special case I guess. I couldn't even tolerate bedcovers in the coldest part of winter!

But also one very good remedy is magnesium. People low in this mineral (found in nuts, beans, yogurt, oatmeal) get muscle cramping and twitching. You can use a topical lotion/cream (which I do now) or a product called SlowMag (WalMart carries it) twice a day, or a good chelate like citrate, gluconate, or glycinate,etc. OXIDE does not work...it is not absorbed and remains in the bowel as a laxative.

When do you take the Baclofen? Right before you go to bed?
If that is the case, try altering your timing and see if that changes anything. Baclofen is a GABA agonist with complex actions.