When the body experiences periods of extreme trauma or stress from thermal injury, sepsis, surgery, or wounds, nonessential amino acids become conditionally essential. The physiological demands of recovery may result in the need for these nonessential amino acids to be greater than the body’s ability to produce them. As a result of these demands, the body’s supply of nonessential amino acids must be provided by the diet.

Arginine
L-Arginine is 32% nitrogen, Nitric oxide is essential for wound healing because it increases the oxygen and blood flow to the wound( vasodilatory, angiogenic), While arginine is the only producer of nitric oxide, 40% of ingested arginine is broken down by the intestines and liver, which reduces the amount available for nitric oxide production. One wound care product is formulated with citrulline, a precursor to arginine. Citrulline circumvents the liver and intestine breakdown, converts to arginine, and increases nitric oxide production.

Studies show that arginine also plays a role in collagen synthesis, and is needed to promote cell division, immune function, and hormone release. It stimulates T-cell responsiveness, helping to prevent infection.

Glutamine
Glutamine functions as a fuel source for fibroblasts and epithelial cells needed for healing. While the safe maximum dosage for glutamine has been established as 0.57 grams per kilogram of body weight, studies on the effectiveness of consuming supplements containing glutamine to heal wounds are inconclusive.

Cystine
Cystine is required to synthesize glutathione, the cell's major antioxidant that plays a key role during tissue repair and collagen synthesis. It promotes positive nitrogen balance by minimizing muscle breakdown and rebuilding lean body mass (LBM).