Which muscle relaxant is used to treat muscle spasms and can be used in an implantable pump device?

• A. Cyclobenzaprine
• B. Baclofen
• C. Methocarbamol
• D. Carisoprodol

Answer: (B)

Baclofen is the muscle relaxant used for treating muscle spasms that can be delivered via an implantable pump. It works as a GABA-B receptor agonist in the spinal cord, lowering the excitability of motor neurons and reducing spasticity. When given intrathecally through a programmable pump, baclofen provides continuous, targeted therapy directly to the spinal fluid, which is particularly helpful for severe spasticity from conditions like spinal cord injury or multiple sclerosis and often allows lower overall dosing with fewer systemic side effects than oral therapy. The other drugs listed are typically used for short-term relief of acute muscle spasms and are not designed for implantable pump delivery.