Baclofen, withdrawal syndrome

Intrathecal - Early symptoms of baclofen withdrawal may include return of baseline spasticity, pruritus, hypotension, and paresthesias. Some clinical characteristics of the advanced intrathecal baclofen withdrawal syndrome may resemble autonomic dysreflexia, infection (sepsis), malignant hyperthermia, neuroleptic-malignant syndrome, or other conditions associated with a hypermetabolic state or widespread rhabdomyolysis. 

Rigoli G, Terrini G, Cordioli Z. Intrathecal baclofen withdrawal syndrome caused by low residual volume in... 

Baclofen, withdrawal syndrome, 26.152 Bambuterol, cardiac failure, 23.181 Benzodiazepines brain damage, 14.36 dependence, 12.41 depression, 17.43 medicolegal aspects, 13.33 Beta2-adrenoceptor agonists, 18.159 asthma, 19.178, 21.179 asthma deaths, 17.164 long-acting, respiratory adverse effects,... 

Colombo G, Addolorato G, Agabio R, et al. Role of GABA(B) receptor in alcohol dependence reducing effect of baclofen on alcohol intake and alcohol motivational properties in rats and amelioration of alcohol withdrawal syndrome and alcohol craving in human alcoholics. Neurotox Res. 2004 6 403-414. 

There is a similarity between baclofen withdrawal and the neuroleptic malignant syndrome. 

This is not the first report of similarities between the neuroleptic malignant syndrome and baclofen withdrawal (18,20,24). In addition, hyperthermia seems to be common in baclofen withdrawal (20). 

Dantrolene is life-saving in mahgnant hyperthermia associated with volatile anesthetics and suxamethonium and is also the drug of choice for the treatment of neuroleptic mahgnant syndrome. Dantrolene has therefore been suggested as an additional therapeutic option in baclofen withdrawal (18), but there is only limited experience (24). In one case of baclofen withdrawal, dantrolene was given with success (24). 

Dantrolene is not likely to be effective for hyperthennia caused by conditions other than muscular hyperactivity, such as increased metabolic rate (eg, salicylate or dinitrophenol poisoning), neuroleptic malignant syndrome (NMS), impaired heat dissipation (eg, anticholinergic syndrome), or environment exposure (heat stroke). However, there is anecdotal evidence (case reports or case-control studies) of benefit for the management of NMS, MAO inhibitor (phenelzine poisoning)-induced hyperthermia, muscle rigidity from baclofen withdrawal, hypertonicity from carbon monoxide poisoning, tetanus, and black widow spider envenomation. 

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