Dipyridamole, a potential therapeutic option for restless legs syndrome: Study
Spain: Dipyridamole is an effective and well-tolerated treatment option for restless legs syndrome (RLS), suggests a recent study published in the journal Movement Disorders.
The study found dipyridamole to have significant therapeutic effects on both sensory and motor symptoms of RLS and on sleep. The findings confirm dipyridamole's efficacy in RLS predicted from preclinical studies and support a key role of adenosine in restless legs syndrome.
There is a need for new pharmacological targets for restless legs syndrome. Preclinical data have suggested an important pathogenetic role of the hypoadenosinergic state. Diego Garcia-Borreguero, Sleep Research Institute, Madrid, Spain, and colleagues aimed to determine whether inhibitors of equilibrative nucleoside transporters, for example, dipyridamole, could provide effective symptomatic treatment.
For this purpose, the researchers conducted a 2-week double-blind, placebo-controlled crossover study in which they assessed the efficacy of dipyridamole (possible up-titration to 300 mg) in untreated patients with idiopathic RLS. After each treatment phase, multiple suggested immobilization tests and polysomnography were performed.
Severity was assessed weekly using the International Restless Legs Rating Scale, Clinical Global Impression, and the Medical Outcomes Study Sleep Scale. The primary endpoint was a therapeutic response.
Twenty-eight of 29 patients recruited were included.
Based on the study, the researchers found the following:
- International Restless Legs Rating Scale scores improved from a mean ± standard deviation of 24.1 ± 3.1 at baseline to 11.1 ± 2.3 at the end of week 2, versus 23.7 ± 3.4 to 18.7 ± 3.2 under placebo.
- Clinical Global Impression, Medical Outcomes Study Sleep, and Multiple Suggested Immobilization Test scores all improved.
- The mean effective dose of dipyridamole was 217.8 ± 33.1 mg/d.
- Sleep variables improved.
- The mean periodic leg movement index at the end of treatment with dipyridamole was 8.2 ± 3.5 versus. 28.1 ± 6.7 under placebo.
- Side effects (dipyridamole vs placebo) included abdominal distension (18% vs. 7%), dizziness (10.7% vs 7.1%), diarrhea, and asthenia (each 7.1% vs 3.6%).
The study titled, "A Randomized, Placebo-Controlled Crossover Study with Dipyridamole for Restless Legs Syndrome," is published in the journal Movement Disorders.