STREPTOMYCIN: CLEARANCE AND BINDING TO PROTEIN

¹ The Research Laboratories of Merck & Co., Inc., Rahway, N. J.
² The Merck Institute for Therapeutic Research, Rahway, N. J.

The renal clearance of streptomycin was measured in dogs. The glomerular filtration rate was simultaneously determined by the clearance of thiosulfate ion. The theoretical relationships of clearance, volume of distribution, and rate of disappearance of the drug from the plasma are correlated with the experimental results.

The streptomycin clearance of man and dog calculated from plasma values was found to be identical per 1.73 m² of surface area.

The clearance was 30 per cent less than the filtration rate.

The low clearance of streptomycin was not due to tubular reabsorption, but to binding of the drug to plasma protein.

Diffusion and ultrafiltration experiments indicate that about 30 per cent of the drug is bound to protein in the range of concentrations used in the clearance experiments.