Baclofen dosage

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%. ... 

The suggested treatment for intrathecal baclofen withdrawal is the restoration of intrathecal baclofen at or near the same dosage as before therapy was interrupted. 

Renal function impairment Because baclofen is primarily excreted unchanged through the kidneys, administer with caution to patients with impaired renal function. Dosage reduction may be necessary. 

Baclofen is at least as effective as diazepam in reducing spasticity and causes less sedation. In addition, baclofen does not reduce overall muscle strength as much as dantrolene. It is rapidly and completely absorbed after oral administration and has a plasma half-life of 3-4 hours. Dosage is started at 15 mg twice daily, increasing as tolerated to 100 mg daily. Adverse effects of this drug include drowsiness however, patients become tolerant to the sedative effect with chronic administration. Increased seizure activity has been reported in epileptic patients. Therefore, withdrawal from baclofen must be done very slowly. 

Clinical trials with oral tizanidine report comparable efficacy in relieving muscle spasm to diazepam, baclofen, and dantrolene. However, tizanidine produces a different spectrum of adverse effects, including drowsiness, hypotension, dry mouth, and asthenia. The dosage requirements vary markedly among patients, and individual dosage titration is necessary to achieve an optimal clinical effect. 

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. 

Drug Baclofen (Lioresal] Oral Dosage Adult 5 mg TID initially increase by 5 mg at 3-day intervals as required maximum recommended dosage is 80 mg/day. Children No specific pediatric dosage is listed the adult dose must be decreased according to the size and age of the child. Comments More effective in treating spasticity resulting from spinal cord lesions (versus cerebral lesions]. 

A second major concern is the possibility that tolerance could develop with long-term, continuous baclofen administration. Tolerance is the need for more of a drug to achieve its beneficial effects when used for prolonged periods. Several studies have reported that dosage must indeed be increased progressively when intrathecal baclofen systems are used for periods of several months to several years.40,63 Tolerance to intrathecal baclofen, however, can usually be dealt with by periodic adjustments in dosage, and tolerance does not usually develop to such an extent that intrathecal baclofen must be discontinued. 

Memantine might modify the effects of antispasmodic drugs such as dantrolene or baclofen and dosage adjustment might be required. ... 

Drug administration route An obstructed catheter connection pin discovered during intrathecal baclofen pump exchange caused increased intrathecal drug dosage requirements and eventually oral baclofen was required [51 ]. 

In a retrospective clinical and radio-graphic review of complications related to intrathecal baclofen and posterior spine fusion in patients with cerebral palsy, the dosage of baclofen did not increase despite the operation [45 ]. 

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