Learn about the side effects of baclofen, from common to rare, for consumers and healthcare professionals. Baclofen is a muscle relaxant used to treat spasticity and muscle pain in conditions like multiple sclerosis and spinal cord injuries by easing nerve signals. It relaxes muscles by reducing nerve activity in the spinal cord. Common side effects include dizziness and drowsiness. Do not drive until you know how baclofen affects you. What is baclofen. In this article, we describe baclofen in more detail, including its uses, how to take it, and the potential side effects and drug interactions. We also answer some frequently asked questions. Baclofen, sold under the brand name Lioresal among others, is a central nervous system (CNS) depressant and derivative of the inhibitory neurotransmitter, gamma -Aminobutyric acid (GABA). [9] Baclofen oral tablet is used to treat muscle spasms. Learn about side effects, warnings, dosage, and more. View baclofen information, including dose, uses, side-effects, renal impairment, pregnancy, breast feeding, contra-indications and important safety information. What is this medication? BACLOFEN (BAK loe fen) treats muscle spasms. It works by relaxing your muscles, which reduces muscle stiffness. It belongs to a group of medications called muscle relaxants. Baclofen is used to help relax certain muscles in your body. It relieves the spasms, cramping, and tightness of muscles caused by medical problems, including multiple sclerosis or certain injuries to the spine. Addolorato G, Leggio L, Ferrulli A, et al. Effectiveness and safety of baclofen for maintenance of alcohol abstinence in alcohol-dependent patients with liver cirrhosis: randomized, double-blind controlled study.