Assessing the efficacy of L-arginine and vitamin C supplementation in pediatric Long-COVID: a Randomized Controlled Trial

ABSTRACT
Following acute SARS-CoV2 infection, both in pediatric and adult populations, lingering or new symptoms may arise, leading to a condition known as Long-COVID.
Understanding the pathophysiological basis of this condition has enabled the identification of supportive therapeutic strategies. Endothelial damage and oxidative stress seem to play a dominant role in the pathogenesis of Long-COVID. These patients experience a relative deficiency of L-arginine, and supplementation of L-arginine may improve endothelial function by promoting the activity of nitric oxide synthase (NOS).
Additionally, vitamin C supplementation could reduce oxidative stress caused by the pro-inflammatory state typical of this condition. In this randomized and controlled trial, we assess the therapeutic effects of the combination of L-arginine and vitamin C in a pediatric population diagnosed with Long-COVID. The primary outcome was to evaluate the improvement in quality of life and changes in scores on the Borg scale, chosen as an indirect indicator of respiratory function. Thirty-six patients were recruited and divided into 3 treatment arms. Results showed improvement in the Borg scale at 30 (p < 0.01) and in quality of life (p < 0.001) among treated vs. untreated patients. Therefore, this supplementation may be considered in the treatment of Long-COVID in the pediatric age group.