Baclofen is used to treat muscle spasms caused by certain conditions (such as multiple sclerosis, spinal cord injury/disease). It works by helping to relax the muscles. Baclofen, sold under the brand name Lioresal among others, is a central nervous system depressant used as a skeletal muscle relaxant. It is primarily used to treat spasticity. It is also used in topical creams to help with pain.