ASD is an extremely distressing disorder for the family and the clinician. It often leads to a divorce due to interpersonal stress. The covered services available are extremely limited. The diagnosis is often missed by the pediatrician resulting in late detection and delayed intervention resulting in critical delays in treatment. Pediatricians often say “boys speak late and will improve with age”. Parents have to fight for services in school and after school the services drop off. There are no FDA approved treatments other than ABA (behavioral therapy with limited effects) resulting in desperation amongst parents often seeking non-standard unproven therapies.
Mechanism of action of Bumetanide: The neurotransmitter GABA plays an important role in the adult nervous system through its inhibitory actions assisting with sensory and cognitive functioning. In the fetus GABA has an excitatory role contributing to normal central nervous system development. Excitatory GABA signaling has been found to persist into adulthood in patients with ASD, chronic pain, brain trauma, epilepsy and other CNS disorders. There is an imbalance in excitatory-inhibitory activity resulting in defects in GABA signaling. Excitatory GABA is associated with high intracellular chloride levels. There is enhanced activity of the Na-K-Cl cotransporter1 leading to increased levels of intracellular chloride resulting in increased neuronal depolarization.
Bumetanide a loop diuretic and may attenuate symptoms of ASD as it is an antagonist of the Na-K-Cl cotransporter 1 reducing intracellular chloride and thus reducing aberrant excitatory GABA signaling.
- The use of bumetanide is certainly a step in the right direction. The dose to try would be similar to the one in the study 0.5 mg bid for ninety days while monitoring for adverse events. I will be trying this strategy in my practice after parent/guardian consent.
- When prescribing this drug for ASD, it is important to discuss the off-label use of bumetanide. I often give a journal reference when using drugs off-label as parents can then get accurate information from “Dr. Google”. It is then a more effective consent process.
- The patients should be monitored for polyuria and hypokalemia as well as other adverse events.
- The is no one medication treatment for ASD and hence this trial using bumetanide most importantly offers hope to these patients and their families which is so important for those afflicted with this debilitating condition.
- References for ASD and treatment issues:
Annals of Clinical Psychiatry VOL 21 NO 3 August 2009 (full issue is on ASD)
Annals of Clinical Psychiatry VOL 21 NO 4 November 2009 (full issue is on ASD)