Define bioavailability (10% of marks). Outline the factors which affect it (90% of marks).
Many candidates spent time defining and describing aspects of pharmacokinetics which were not relevant to the question. E.g. clearance, volume of distribution and half-life. Candidates who scored well utilised a structure which incorporated the headings of the factors which affect the bioavailability of medications with a simple description as to the nature of the effect. These factors included: the physical properties of the drug, the preparation, patient factors, the route of administration and metabolism amongst others.
Generic influences on drug bioavailability
|
Factors affecting first pass metabolism
|
||
Factors affecting gastrointestinal absorption
|
Bioavailability via transdermal and mucosal routes of administration
|
Wesch, Roland. "Absolute and relative bioavailability." Drug Discovery and Evaluation: Methods in Clinical Pharmacology. Springer Berlin Heidelberg, 2011. 173-180.
Vaughan, D. P. "A model-independent proof of Dost's law of corresponding areas." Journal of pharmacokinetics and biopharmaceutics 5.3 (1977): 271-276.
Branson, Herman. "The kinetics of reactions in biological systems." Archives of biochemistry and biophysics 36.1 (1952): 48-59.
Dost, F. H. "Absorption, Transit, Occupancy und Availments als neue Begriffe in der Biopharmazeutik." Journal of Molecular Medicine 50.8 (1972): 410-412.
Balant, L. P. "Is there a need for more precise definitions of bioavailability?." European Journal of Clinical Pharmacology 40.2 (1991): 123-126.
Rescigno, Aldo. "Bioequivalence." Pharmaceutical research 9.7 (1992): 925-928.
Koch-Weser, Jan. "Bioavailability of drugs." New England Journal of Medicine 291.10 (1974): 503-506.
Allam, Ahmed N., S. S. El Gamal, and V. F. Naggar. "Bioavailability: A pharmaceutical review." Int J Novel Drug Deliv Tech 1.1 (2011): 77-93.
Pond, Susan M., and Thomas N. Tozer. "First-pass elimination basic concepts and clinical consequences." Clinical pharmacokinetics 9.1 (1984): 1-25.
De Paepe, Peter, Frans M. et al "Pharmacokinetic and pharmacodynamic considerations when treating patients with sepsis and septic shock." Clinical pharmacokinetics 41.14 (2002): 1135-1151.