Common side effects include sleepiness, weakness, and dizziness.[8] Serious side effects may occur if baclofen is rapidly stopped including seizures and rhabdomyolysis.[8] Use in pregnancy is of unclear safety while use during breastfeeding is probably safe.[14] It is believed to work by decreasing levels of certain neurotransmitters.[8]
The adverse effects and safety profile associated with baclofen when it is combined with sedative drugs (for example alcohol or benzodiazepines) range depending on the dose and the individual. The interaction may increase the sedative effects of all ingested sedatives and as such is not generally recommended.[15] In high doses the interaction can cause de novo seizures.[16]
Baclofen was approved for medical use in the United States in 1977.[8] It is available as a generic medication.[9][17] In 2022, it was the 104th most commonly prescribed medication in the United States, with more than 6million prescriptions.[18][19]
^Ahmadi-Abhari SA, Akhondzadeh S, Assadi SM, Shabestari OL, Farzanehgan ZM, Kamlipour A (February 2001). "Baclofen versus clonidine in the treatment of opiates withdrawal, side-effects aspect: a double-blind randomized controlled trial". Journal of Clinical Pharmacy and Therapeutics. 26 (1): 67–71. doi:10.1111/j.1365-2710.2001.00325.x. PMID11286609. S2CID28295723.