Many people with MS have problems with spasticity, a condition that primarily affects the lower limbs. Spasticity can occur either as a sustained stiffness caused by increased muscle tone or as spasms that come and go, especially at night. It is usually treated with muscle relaxants and tranquilizers. Baclofen (Lioresal), the most commonly prescribed medication for this symptom, may be taken orally or, administered via a surgically implanted pump that provides timed dosage release.. Tizanidine (Zanaflex), used for years in Europe and now approved in the United States, appears to function similarly to Baclofen. Diazepam (Valium), clonazepam (Klonopin), and dantrolene (Dantrium) can also reduce spasticity. Although its beneficial effect is temporary, physical therapy may also be useful and can help prevent the irreversible shortening of muscles known as contractures. Surgery to reduce spasticity is seldom appropriate in MS. In some severe cases a pump may be implanted for efficient delivery of timed measured doses of Baclofen.