Background: Weight loss is often prescribed for patients with Obstructive Sleep Apnoea (OSA) to aid in reducing the severity of the disorder. However, most weight loss attempts are unsuccessful without professional supervision. Anti-obesity medications can be expensive, and cheaper medications are required. Dexamfetamine (DEX), could be a suitable alternative. The aim of this study is to test whether a 6 month treatment of DEX is more effective than placebo in treating obesity and reducing the severity of OSA.

Methods: Double blind randomised placebo-controlled trial of 6 months treatment followed by 2 years observation, with 2 groups of 30 participants per group. Participants are randomised 1:1 to either immediate release DEX tablets or identical placebo tablets. The dose is titrated to a maximum of 30mg/6 tablets twice daily. Each participant is reviewed weekly during titration followed by monthly review at maintenance. Dosage adjustment is guided by clinical effects and ratings using the amphetamine interview rating scale. Overnight sleep study is performed pre and post treatment.

Results: The data remains blinded and is the combination of DEX and placebo groups. 52 subjects have been consented into the study (33 male, mean age 47 years). Mean weight loss at 6 months was 9.04 kg (95% CI 6.29 ? 11.77, p<0.001). Mean reduction in AHI was 7.81 (95% Cl -1.81 ? 17.44, p=0.108). Mean reduction in oxygen desaturation index (ODI) was 12.85 (95% Cl 1.34 ? 24.35, p=0.030). 

Conclusions: The preliminary results suggest DEX may be a cheaper alternative to newer appetite supression drugs and merits further research.