Hallucination baclofen

Abrupt discontinuation of baclofen may produce hallucinations and seizures. 

An 82-year-old man with left ventricular dysfunction and gout had worsening renal function (33). He was taking lisinopril, furosemide, naproxen, allopurinol, and baclofen 20 mg tds. As no reason could be found for the use of baclofen the dose was halved and then stopped 10 days later. The next day he had visual hallucinations, confusion, and agitation, and required sedation with diazepam. He was afebrile, with normal inflammatory markers, and a CT scan of the brain showed only cerebral atrophy. Baclofen was reintroduced, with complete resolution of neuropsychiatric symptoms within 48 hours. 

Lees AJ, Clarke CRA, Harrison MJ. Hallucinations after sudden withdrawal of baclofen. Lancet 1977 2(8027) 44-5. 

Baclofen must be tapered off when being discontinued. Abrupt withdrawal after prolonged use can cause anxiety, agitated behavior, hallucinations, severe tachycardia, acute spasticity, and seizures. 

Baclofen is an agonist at the GABA(B) receptor and can produce profound CNS and respiratory depression as well as paradoxic muscle hypertonicity and seizure-like activity. Hallucinations, seizures, and hyperthermia have occurred after abmpt withdrawal from baclofen. 

Unpleasant adverse effects (hallucinations, confusion, headache, nausea) and worsening of the symptoms of parkinsonism have occurred in patients on levodopa who were given baclofen. 

Twelve patients with parkinsonism on levodopa plus a dopa-decarboxylase inhibitor were additionally given baclofen. The eventual baclofen dosage was intended to be 90 mg daily, but the adverse effects were considerable (visual hallucinations, a toxic confusional state, headaches, nausea) so that only 2 patients reached this dosage, and 2 patients withdrew because they could not tolerate these adverse effects. The mean dosage for those who continued was 45 mg daily. Rigidity was aggravated by an average of 46% and functional capacity deteriorated by 21%. ... 

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