Levodopa Baclofen

Opioids, benzodiazepines, barbiturates, corticosteroids, dopamine agonists (e.g., amantadine, bromocriptine, levodopa, pergolide, pramipexole, ropinirole), H2-receptor antagonists, anticholinergics (e.g., diphenhydramine, trihexylphenidyl), P-adrenergic blockers, clonidine, methyldopa, carbamazepine, phenytoin, baclofen, cyclobenzaprine, lithium, antidepressants (e.g., tricyclic antidepressants, selective serotonin reuptake inhibitors), and interleukin-2... 

The pharmacologic basis of these disorders is unknown, and there is no satisfactory medical treatment for them. A subset of patients respond well to levodopa medication (dopa-responsive dystonia), which is therefore worthy of trial. Occasional patients with dystonia may respond to diazepam, amantadine, antimuscarinic drugs (in high dosage), carbamazepine, baclofen, haloperidol, or phenothiazines. A trial of these pharmacologic approaches is worthwhile, though often not successful. Patients with focal dystonias such as blepharospasm or torticollis often benefit from injection of botulinum toxin into the overactive muscles. The role of deep brain stimulation for the treatment of these conditions is being explored. 

LEVODOPA MUSCLE RELAXANTS-BACLOFEN Reports of CNS agitation and i efficacy of levodopa Uncertain Avoid co-administration... 

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%. ... 

Information appears to be limited to these reports, but they suggest that baclofen should be used very cautiously in patients taking levodopa. 

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