The level of total amino acids was determined in plasma and urine in cases suffering from ocdematous forms of PCM before and after receiving a single dose of each of cysteine, tryptophan and lysine. The increase in plasma amino acids following dosing was less in malnourished cases than in controls. Fasting urinary amino acid content in malnourished subjects was higher than in controls and so was also the ratio of urine amino acids collected after dosing to the fasting level. As the study revealed that protein depletion inhibits intestinal absorption and tubular reabsorption, parenteral administration of amino acids is recommended during treatment to escape intestinal loss. Excess oral protein should be given in food to compensate for losses via the gastro-intestinal and renal tracts.