Pharmacological complications of the chronic baclofen infusion in the severe spinal spasticity. Personal experience and review of the literature.
OBJECTIVE
To evaluate the pharmacological complications and side effects of the chronic intrathecal baclofen infusion in patients suffering from intractable spinal spasticity in our Department as well as in the literature.


METHODS
The pharmacological complications and side effects observed at long-term follow-up in 25 patients with chronic intrathecal baclofen infusion are evaluated; the search of the literature complications was carried out in Medline and in Ingenta web sites.


RESULTS
We have been able to observe in our series 3 (12%) patients with hypotonia, 2 with impairment on erection (8%) and 1 (4%) with constipation; 5 (20%) patients showed also tolerance but only 1 (4%) needed a ''drug holiday''. In the literature the side effects range from 4% to 16%. Moreover the tolerance is reported from 3% to 15%. The overdose has been reported from 0% to 14%, while the syndrome of withdrawal is reported in 16 patients with 6 fatalities. In our series these two last complications were not observed.


CONCLUSIONS
Lethal pharmacological complications are rare and, if promptly diagnosed and treated, are reversible. Side effects of minor importance can impair the patient quality of live and needed to be adjusted to patient's requirements. This kind of therapy should be restricted to specialized centres.
Dario
A
A
Neurosurgical Clinic, University of Insubria, University Hospital of Varese, Italy. dario.alessandro@virgilio.it
Scamoni
C
C
Picano
M
M
Casagrande
F
F
Tomei
G
G
D000328:Adult; D001418:Baclofen / Q000008:administration & dosage / Q000009:adverse effects*; D003248:Constipation / Q000139:chemically induced / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D062787:Drug Overdose / Q000503:physiopathology / Q000517:prevention & control; D004361:Drug Tolerance / Q000502:physiology; D007172:Erectile Dysfunction / Q000139:chemically induced / Q000503:physiopathology; D005260:Female; D018755:GABA Agonists / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D015918:Infusion Pumps, Implantable / Q000009:adverse effects; D007278:Injections, Spinal / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009123:Muscle Hypotonia / Q000139:chemically induced / Q000503:physiopathology; D009128:Muscle Spasticity / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D013118:Spinal Cord Diseases / Q000150:complications* / Q000503:physiopathology; D013119:Spinal Cord Injuries / Q000150:complications* / Q000503:physiopathology; D013375:Substance Withdrawal Syndrome / Q000150:complications* / Q000503:physiopathology; D016896:Treatment Outcome
D018755:GABA Agonists; D001418:Baclofen