The drug bumetanide, which has been used for decades to treat high blood pressure and other conditions, has now shown some promise in a small clinical trial for autism spectrum disorder. The drug reduced the overall severity of behavioral symptoms after 3 months of daily treatment.
The scientists published their findings in the journal Translational Psychiatry. Parents of the children who were treated reported that their children were more present and engaged in social interactions after taking the drug.
Autism interferes with the neurotransmitter GABA, which has the effect of dampening neural activity. Bumetanide could enhance the inhibitory effects of GABA and the drug has been used safely as a diuretic to treat a wide range of heart, lung, and kidney conditions. The scientists used a pool of 60 autistic children between the ages of 3 and 11, and randomly assigned them a daily pill of bumetanide or a placebo. The study was double-blind.
The children who got bumetanide improved by 5.6 points on a 60-point scale that’s used to assess behaviors related to autism spectrum disorder. That was enough to nudge the group average under the cutoff for severe autism and into the mild to medium category. The study didn’t look at whether the drug improve all symptoms equally, or some more than others.
Communication and social interactions were notably improved. This study and others suggest that drugs reducing the neural excitation by blocking glutamate or enhancing inhibition by boosting GABA may be helpful for treating autism.