There’s a clinical trial underway by the National Institutes of Health Clinical Center to determine whether dextromethorphan can help treat diabetic macular edema.

Briefly, a frequent manifestation of diabetic retinopathy (DR) is diabetic macular edema (DME) for which the only proven treatment is laser photocoagulation. In the retina, microglia ^[1] are capable of migrating through the retina to sites of inflammation to associate closely with neurons and the vasculature, and are key cellular players in the processes of chronic inflammation implicated in DME. For these reasons, microglia represent a promising cellular target for forms of therapy that limit the inflammatory changes found in DR.

The objective of the trial is to investigate the safety and efficacy of dextromethorphan as a microglia inhibitor to help prevent the inflammation and swelling present in DME. Dextromethorphan is approved for use as a cough medicine, but it has not been studied to see if it can help in diabetic macular edema.

Click here ^[2] for further details about the trial and participation eligibility.