NeuroTalk Support Groups - Baclofen Injections Used to Treat RSD And Dystonia's

Dear Alison -

Although I don't have any personal experience with intramuscular injections of Baclofen, I've been taking 50 mg./day orally for years and your question drew my interest. One of the key things about Baclofen is the importance of maintaining a nearly constant level of the medication in the body. For a start, we have the form the US Food and Drug Administration approved package insert for oral Baclofen:

WARNINGS

a. Abrupt Drug Withdrawal: Hallucinations and seizures have occurred on abrupt withdrawal of baclofen. Therefore, except for serious adverse reactions, the dose should be reduced slowly when the drug is discontinued. . . . [Emphasis added.]

http://pi.watson.com/data_stream.asp...=pi&language=E

And for possibly the most extreme case in this regard, see the following:

Prolonged severe withdrawal symptoms after acute-on-chronic baclofen overdose, Peng CT, Ger J, Yang CC, Tsai WJ, Deng JF, Bullard MJ, J Toxicol Clin Toxicol. 1998;36(4):359-63:

Abstract

INTRODUCTION: Baclofen is frequently used to treat muscle spasticity due to spinal cord injury and multiple sclerosis. Baclofen overdose can lead to coma, respiratory depression, hyporeflexia, and flaccidity. An abrupt decrease in the dose of baclofen due to surgery or a rapid tapering program may result in severe baclofen withdrawal syndrome manifesting hallucinations, delirium, seizures, and high fever. Severe baclofen withdrawal syndrome secondary to intentional overdose, however, has not received mention.

CASE REPORT: A 42-year-old male receiving chronic baclofen therapy, 20 mg/d, attempted suicide by ingesting at least 800 mg of baclofen. He was found in coma 2 hours postingestion with depressed respirations, areflexia, hypotonia, bradycardia, and hypotension. Treatment with intravenous fluids, atropine, dopamine, and hemodialysis was associated with restoration of consciousness within 2 days but disorientation, hallucinations, fever, delirium, hypotension, bradycardia, and coma developed during the following week. Baclofen withdrawal syndrome was not diagnosed until hospital day 9, when reinstitution of baclofen rapidly stabilized his condition. Oral overdosage of baclofen causes severe neurological and cardiovascular manifestations due to its GABA and dominant cholinergic effects. Severe baclofen withdrawal syndrome is manifest by neuropsychiatric manifestations and hemodynamic instability. Caution should be exercised after a baclofen overdose in patients receiving chronic baclofen therapy.

PMID: 9711203 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/9711203

It may then come as little surprise that in a few hours of research on PubMed http://www.ncbi.nlm.nih.gov/pubmed/ in preparing this post, while I found hundreds of articles dealing with the delivery of Baclofen by means other than oral tablets, all nevertheless required the continuous delivery of the medication, either "intrathecally" or "intraventricularly" to the spine, in relatively minute dosages. See, e.g. Intrathecal baclofen for dystonia of complex regional pain syndrome, van Rijn MA, Munts AG, Marinus J, Voormolen JH, de Boer KS, Teepe-Twiss IM, van Dasselaar NT, Delhaas EM, van Hilten JJ, Pain 2009 May;143(1-2):41-7. Epub 2009 Feb 18 FREE FULL TEXT @ http://www.rsds.org/2/library/articl...G_MarinusJ.pdf :

Abstract

Dystonia in complex regional pain syndrome (CRPS) responds poorly to treatment. Intrathecal baclofen (ITB) may improve this type of dystonia, but information on its efficacy and safety is limited. A single-blind, placebo-run-in, dose-escalation study was carried out in 42 CRPS patients to evaluate whether dystonia responds to ITB. Thirty-six of the 38 patients, who met the responder criteria received a pump for continuous ITB administration, and were followed up for 12 months to assess long-term efficacy and safety (open-label study). Primary outcome measures were global dystonia severity (both studies) and dystonia-related functional limitations (open-label study). The dose-escalation study showed a dose-effect of baclofen on dystonia severity in 31 patients in doses up to 450 microg/day. One patient did not respond to treatment in the dose-escalation study and three patients dropped out. Thirty-six patients entered the open-label study. Intention-to-treat analysis revealed a substantial improvement in patient and assessor-rated dystonia scores, pain, disability and quality-of-life (Qol) at 12 months. The response in the dose-escalation study did not predict the response to ITB in the open-label study. Eighty-nine adverse events occurred in 26 patients and were related to baclofen (n=19), pump/catheter system defects (n=52), or could not be specified (n=18). The pump was explanted in six patients during the follow-up phase. Dystonia, pain, disability and Qol all improved on ITB and remained efficacious over a period of one year. However, ITB is associated with a high complication rate in this patient group, and methods to improve patient selection and catheter-pump integrity are warranted.

PMID: 19232828 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/19232828

AND

The incidence and management of tolerance in intrathecal baclofen therapy, Heetla HW, Staal MJ, Kliphuis C, van Laar T, Spinal Cord. 2009 Oct;47(10):751-6. Epub 2009 Mar 31.

Abstract

STUDY DESIGN: Retrospective study. OBJECTIVES: To study the incidence and management of tolerance in patients treated with intrathecal baclofen (ITB) therapy.

SETTING: Department of neurology and neurosurgery, University Medical Center Groningen, The Netherlands.

METHODS: Medical records of all patients who had received an implantable ITB pump at our clinic during 1991-2005 were reviewed.

RESULTS: A total of 37 patients (representing 116 pump years) were included. Mean follow-up time was 38 months (range 3-120 months). Baclofen dose increased in the first 18 months after implantation (P<0.05), and then stabilized around a mean dose of 350 microg per day. Eight patients (22%) developed tolerance, defined as a dose increase of >100 microg per year. No predictive factors for development of tolerance could be determined. Three different treatment regimens for tolerant patients were analyzed. Altering the infusion mode from simple to complex continuous (n=6) had no effect on the development of tolerance. Pulsatile bolus infusion (n=1) and a drug holiday (n=2) were both effective in reducing the daily baclofen dose. Patients who needed surgical revision of the pump system because of mechanical failures (n=11) showed a significant dose decrease during the first month after revision, indicating that the preoperative dose increase most likely had been caused by the pump failure. Pump-related complications occurred once per 10.5 years of ITB treatment. Drug-related side effects had an annual risk of 13.8%. The reported events were mostly mild.

CONCLUSIONS: ITB therapy is effective and safe, also in the long term and causes tolerance in only 22% of the treated patients.

PMID: 19333246 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/19333246

AND

Intraventricular baclofen for dystonia: techniques and outcomes. Clinical article, Albright AL, Ferson SS, J Neurosurg Pediatr. 2009 Jan;3(1):11-4:

Abstract

OBJECT: The aim of this study was to evaluate the use of intraventricular baclofen (IVB) for the treatment of severe generalized secondary and heredodegenerative dystonia. METHODS: Nine children and 1 adult with severe dystonia unresponsive to multiple oral medications were treated with IVB. Intraventricular catheters were positioned endoscopically in the third ventricle. RESULTS: Eight of the 10 patients responded to IVB; their mean dystonia scores on the Barry-Albright dystonia scale decreased from 23 to 8. The 2 patients who did not respond had not responded to previous high doses of intrathecal baclofen. No adverse side effects related to IVB occurred. One child developed a pump infection that required pump removal, 1 developed a CSF infection that cleared after antibiotic administration, and 1 developed ventriculomegaly that required a shunt placement.

CONCLUSIONS: Intraventricular baclofen is an effective method of infusing baclofen to treat severe, generalized secondary dystonia, and, at times, heredodegenerative dystonia. The site of baclofen's activity when treating dystonia may be at the cortical level, and intraventricular infusion may result in higher baclofen concentrations over the cortex than intrathecal infusion. Additional studies are necessary to determine whether IVB is effective at lower doses than those used with intrathecal baclofen administration.

PMID: 19119897 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/19119897

Bottom line: before you allow any intramuscular administration of Baclofen, you should ask your doctor what are his or her plans for maintaining as close to constant level of the medication while s/he gives you intramuscular injections.

On an somewhat unrelated matter, I keep running across the name of Candida (Candy) McCabe, PhD, RGN and her colleagues in the CRPS programme of the Royal National Hospital for Rheumatic Diseases and University of Bath. Bath, UK. I expect with your experience over too many years and the energy which you have brought to bear, you are familiar with Dr. McCabe’s unit, which I recall correctly treated our old friend Rosie at one time, but for those who are not, general information can be found at http://www.rnhrd.nhs.uk/departments/...n_syndrome.htm Dr. McCabe is of course a pioneer in the use of mirror visual feedback in the treatment of CRPS-1 and while the document describing in-patient treatment in her unit is fairly typical of first-rate rehabilitative facilities http://www.rnhrd.nhs.uk/departments/...ationSheet.pdf it does mention that patients may hay the option of participating in motor visual feedback trials. Unfortunately, it appears to be accepted as conventional wisdom that motor visual feedback therapy, while promising in cases of acute and intermediate CRPS-1 is not effective in cases of chronic CRPS, where cortical reorganization as already occurred. See, Systematic review of the effectiveness of mirror therapy in upper extremity function, Ezendam D, Bongers RM, Jannink MJ, Disabil Rehabil 2009;31(26):2135-49 at 2144 FREE FULL TEXT OF Epub version @ http://www.rsds.org/2/library/articl...rs_Jannink.pdf [p. 9 of Epub doc], citing, A controlled pilot study of the utility of mirror visual feedback in the treatment of complex regional pain syndrome (type 1), McCabe CS, Haigh RC, Ring EFJ, Halligan PW, Wall PD, Blake DR, Rheumatology 2003; 42:97-101, FREE FULL TEXT @ http://www.rsds.org/2/library/articl..._Ring_etal.pdf

Nevertheless, where Dr. McCabe and her team may well be the leading experts on CRPS in the UK, I would urge you to consider contacting her through one of the various means set forth in the general information page on her unit at Bath, regarding any available treatment options for your dystonia, unless you have already done so. And of course, for all I know, that's where you may be receiving treatment. :)

Good luck!

Mike