Describe the characteristics of a drug that influence its excretion by the kidneys
Drug characteristics that might influence the renal excretion processes include charge, size,
solubility, and binding to specific structures or protein. Whether the drug is unchanged versus
metabolised can influence these factors.
This question tests core knowledge of pharmacology principles and should be answered with
equations, graphs or simple clear descriptions of physical and chemical principles. Extended
examples and hedged statements about “influencing” without the direction, magnitude and
necessary conditions for the influence did not score marks.
The college answer being unstructured and incomplete, the trainee is left to construct his own in a vacuum devoid of senior guidance. A well-structured answer would probably benefit from splitting the characteristics into the three major components which make up renal clearance, those being glomerular filtration, active secretion, passive reabsorption and intrinsic renal metabolism.
Drug characteristics which influence its glomerular filtration
Drug characteristics which influence its active secretion
Drug characteristics which influence its passive resorption
Other drug characteristics which influence renal clearance
Miners, J. O., et al. "The Role of the Kidney in Drug Elimination: Transport, Metabolism and the Impact of Kidney Disease on Drug Clearance." Clinical Pharmacology & Therapeutics (2017).
Mahasen, Laila M. Aboul. "Evolution of the Kidney." Anatomy Physiol Biochem Int J 1(1) : APBIJ.MS.ID.555554 (2016)
Brater, D. Craig. "Measurement of renal function during drug development." British journal of clinical pharmacology 54.1 (2002): 87-95.
Levy, Gerhard. "Effect of plasma protein binding on renal clearance of drugs." Journal of pharmaceutical sciences 69.4 (1980): 482-483.
Regårdh, Carl G. "Factors contributing to variability in drug pharmacokinetics. IV. Renal excretion." Journal of Clinical Pharmacy and Therapeutics 10.4 (1985): 337-349.
Miner, Jeffrey H. "The glomerular basement membrane." Experimental cell research 318.9 (2012): 973-978.
Elwi, Adam N., et al. "Renal nucleoside transporters: physiological and clinical implications This paper is one of a selection of papers published in this Special Issue, entitled CSBMCB—Membrane Proteins in Health and Disease." Biochemistry and cell biology 84.6 (2006): 844-858.
Nigam, Sanjay K., et al. "Handling of drugs, metabolites, and uremic toxins by kidney proximal tubule drug transporters." Clinical journal of the American Society of Nephrology 10.11 (2015): 2039-2049.
Bendayan, Reina. "Renal drug transport: a review." Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy 16.6 (1996): 971-985.
Birnbaum, Jerome, et al. "Carbapenems, a new class of beta-lactam antibiotics: Discovery and development of imipenem/cilastatin." The American journal of medicine 78.6 (1985): 3-21.
Lohr, James W., Gail R. Willsky, and Margaret A. Acara. "Renal drug metabolism." Pharmacological Reviews 50.1 (1998): 107-142.
Bott, Phyllis A., and A. N. Richards. "The passage of protein molecules through the glomerular membranes." Journal of Biological Chemistry 141.1 (1941): 291-310.