Effect of ascorbic acid on urinary hydroxyproline of children receiving corticosteroids.

Oral administration of ascorbic acid, 0·5 g every 8 hours for a period of 4 days, had no effect on the urinary hydroxyproline excretion of 7 healthy children aged 8 to 14 years. When the same medication was given to 8 children aged 9 to 14 years who were receiving large doses of prednisolone (2 mg/kg per 24 hr) for a period of at least 15 days before as well as during ascorbic acid administration, a rise in the urinary hydroxyproline excretion was observed (from a mean value of 44±4·1 SE before to 67±4·6 mg/24 hr on the 4th day of ascorbic acid administration, P <0·001). Urinary hydroxyproline excretion of 3 children 4 days after stopping ascorbic acid administration, while still on prednisolone, had returned to the level observed before ascorbic acid.