Tolerability of High-dose Baclofen in the Treatment of Patients with Alcohol Disorders: A Retrospective Study.

AIMS The aim of this study was to describe the tolerability of high-dose baclofen taken by patients with alcohol disorders during their first year of treatment. METHODS The medical records of all patients prescribed baclofen by one general practitioner were examined and all patients who could be contacted were retrospectively interviewed about adverse effects. RESULTS Of the 146 eligible patients, 116 (79%) could be interviewed. Ninety (78%) reported at least one adverse effect (mean number per patient: 2.8 ± 2.7). The mean dosage of baclofen at the onset of the first adverse effect was 83 ± 57 mg/day. The most frequent group of adverse effects involved disruption of the wake-sleep cycle and affected 73 patients (63%). Persistent adverse effects occurred in 62 patients (53%). Eight patients (7%) had adverse effects that led them to stop taking baclofen. Their dosages were <90 mg/day at that time. Alertness disorders and depression were the adverse effects that most frequently led to stopping baclofen. Bouts of somnolence and hypomanic episodes were the most potentially dangerous adverse effects. Women reported significantly more adverse effects than men. CONCLUSION High-dose baclofen exposes patients with alcohol disorders to many adverse effects. Generally persistent, some adverse effects appear at low doses and may be dangerous.