Does Intrathecal Glycine Help in the Pain and Dystonia of Complex Regional Pain Syndrome I (RSD)?

Bernard M. Abrams, MD

Intrathecal glycine (ITG) was considered as a possible ameliorating agent in complex regional pain syndrome (CRPS) because glycinergic neurotransmission plays an important inhibitory role in the processing of sensory and motor information.  

The safety and efficacy of ITG treatment was studied for four weeks in CRPS patients with dystonia in the period before they received intrathecal baclofen treatment. Twenty patients were assessed, and after exclusion of one patient, the remaining 19 patients were randomized in a double-blind placebo-controlled crossover study.

Although there was a worsening trend on the Clinical Global Impression (CGI)  and Patient’s Global Impression (PGI) score during ITG treatment, there were no significant differences between ITG and placebo treatment in any of the outcomes. ITG given over four weeks was ineffective for pain or dystonia in CRPS. Although no serious adverse events occurred, further studies are required to rule out potential neurotoxicity of ITG.

Alexander G. Munts a, Anton A. van der Plas a, Joan H. Voormolen b, Johan Marinus a, Irene M. Teepe Twiss c,Willem Onkenhout d, Joop M. van Gerven a,e, Jacobus J. van Hilten a,*

Intrathecal glycine for pain and dystonia in complex regional pain syndrome

PAIN 146 (2009) 199–204