What is Pain-O-Soma 350mg? Pain-O-Soma 350mg is a prescription muscle relaxant that contains Carisoprodol as its active ingredient. It is used to relieve mus spasmscle, acute musculoskeletal pain, and injury-related stiffness. Pain-O-Soma works by blocking pain sensations between the nerves and the brain. How Does Pain-O-Soma 350mg