Conversely, for patients with an IMD for which arginine is commonly supplemented (e.g. MELAS, argininosuccinate lyase deficiency, argininosuccinate synthetase deficiency, ornithine transcarbamylase deficiency) or for patients undergoing a growth hormone‐releasing hormone (GHRH)‐arginine stimulation test to evaluate for growth hormone deficiency, this scenario could result in a provider incorrectly presuming appropriate administration and/or supplement compliance. The gene discussed is ASS1; the disease is MELAS.