Viagra Shows Promise in Treating Rare Childhood Metabolic Disease
Researchers are investigating whether sildenafil, the active ingredient in Viagra, can alleviate symptoms of Leigh syndrome, a rare and often fatal genetic disorder affecting children. A small pilot study conducted by researchers at Charité – Universitätsmedizin Berlin, Heinrich Heine University Düsseldorf, and the Fraunhofer Institute for Translational Medicine and Pharmacology, has shown promising results, according to a report from Nationale Zorggids.
Leigh syndrome is a severe neurological disorder that typically manifests in infancy or early childhood. It results from a disruption in cellular energy production, leading to progressive loss of motor and cognitive functions. Symptoms include seizures, muscle weakness, paralysis, and developmental delays. Currently, there is no approved cure for Leigh syndrome, and the prognosis is generally poor, with most children not surviving beyond their early years.
The study, involving six patients aged between 9 months and 38 years, found that administering sildenafil for several months led to improvements in muscle strength and, in some cases, a reduction in neurological symptoms. Patients also demonstrated a faster recovery from metabolic crises, periods of severe energy imbalance that are characteristic of the disease. These findings were initially reported by MedicalXpress on March 17, 2026.
The unexpected potential of sildenafil stems from its known function as a vasodilator – a substance that widens blood vessels. Whereas primarily recognized as a treatment for erectile dysfunction in adults, sildenafil is already used in children to treat pulmonary hypertension, a condition involving high blood pressure in the lungs. Researchers theorize that the drug’s ability to improve blood flow may help to restore energy balance in cells affected by Leigh syndrome.
Further research, including laboratory experiments on patient-derived cells and animal models, has supported these initial findings. According to a report by Headliner.nl, scientists observed activation of genes crucial for brain development, partial reversal of damaging molecular changes, stimulation of nerve cell growth, and improved energy metabolism in laboratory settings. In animal models—mice and pigs with similar genetic mutations—sildenafil extended lifespan.
Dr. Markus Schuelke, and Dr. Alessandro Prigione, involved in the research, have cautioned that the evidence remains preliminary and that large-scale clinical trials are necessary to definitively establish the drug’s efficacy and safety. However, the existing experience with long-term sildenafil use in children with pulmonary arterial hypertension could potentially expedite its approval for Leigh syndrome treatment.
A separate study by McGill University Health Centre, reported by Scientias.nl in February 2024, explored the use of sildenafil in treating brain damage caused by oxygen deprivation in newborns. That study also indicated the drug was safe and potentially effective in promoting recovery, suggesting a broader therapeutic potential for sildenafil in pediatric neurological disorders.
Given the rarity of Leigh syndrome—affecting approximately one in 36,000 children—conducting extensive research presents significant challenges. Researchers are currently planning larger clinical trials to confirm the initial findings and determine the optimal dosage and treatment duration for sildenafil in patients with Leigh syndrome. No timeline for the commencement of these trials has been publicly announced.