Pharmacodynamics & Pharmacokinetics
2011a(3) Outline the effects of liver failure on drug kinetics and dynamics
2002b(2)Briefly describe the factors affecting the uptake of an orally administered drug
2000a(14)Discuss roles of plasma esterases on drugs used in anaesthesia
1995b(13)Give a brief account of drug protein binding and outline its significance
Primary Examination SAQs 
Hi Amanda,
Thanks again for a great site, your answer to 2006a(2)/00b(9): What is an isomer? states – 2 different types exist: structural and optical isomers.
Most text books divide isomers into structural isomerism and stereo isomerism with other branches under these two main headings. E.g. Peck page 45.
Cheers, Graham
Graham Wesley
December 9, 2010 at 2:26 pm
Hi Graham
Thanks for the support for the website – I am glad that you are utilising it! I have changed the wording in the isomer question – thanks for picking up the typo!
Good luck with the study!
Amanda
primarysaqs
December 9, 2010 at 7:11 pm
Hi Amanda! I’ve been using your site a lot lately, thanks, it is great! I can’t seem to find a worked out answer or good textbook reference for this question from 2009(b): ” Describe the effect of obesity on pharmacokinetics and the potential clinical implications, providing relevant examples.” I worked out a 2 page answer which I would like to compare with others and get some feedback, I am not quire sure if this is good enough but generally tried to follow the examiners feedback for a bit of help. If you are interested in this answer, or if you know where I can find this answer, please email (theodevries@doctors.org.uk) or facebook me.
Thanks!
Theo
Theo de Vries
October 18, 2011 at 3:53 pm
No problems
Email me the answer and I will get back to you ASAP! Try to limit your answer to 1 page to get the most important points..
There are some Oxford Mini Books, and the CEACCP articles on Obesity and Anaesthesia and recent BJA articles (supplement from 2010) on the subject which are very comprehensive.
Good luck!
primarysaqs
October 18, 2011 at 7:41 pm
Hi Amanda,
Youve done a wonderful job with the site.
Quick question. With regards to protiein binding in 1995b(13), when you put down ionic or electrostatic, did you mean “ionic or covalent”? I beleive that electrostatic is the type of bond and ionic or covalent are the subset of bond types.
luke
April 3, 2012 at 9:35 pm
Hi Luke
Covalent, ionic and electrostatic (or Van de Waals) bonding are three distinct types of bonds.
Covalent is the type of bonding keeping atoms joined together to make up molecules such as proteins. They are strong bonds that are not involved in most dynamic protein-drug interactions but can occur with irreversible interactions such as non-competitive binding of phenoxybenzamine with the alpha 1 receptor or PPI’s with the proton pump in the stomach.
Ionic bonds involve ionised molecules, either positive or negatively charged through losing or gaining electrons respectively. These bonds are relevant to proteins as they are generally negatively charged and therefore attract and repel positive and negatively charged molecules respecitively. For example Ca2+ and H+ compete for binding sites on Albumin and can displace each other where there concentrations change.
Electrostatic or Van de Waals bonds are the weakest type and involve electrical dipoles forming in uncharged molecules dues to an imbalance in electron attraction between atoms. A good example is water which has a particularly strong electrical dipole due to the H-O bond which is often referred to as a “hydrogen bond”. This is still a subset of electrostatic bonds. This is relevant for protein binding as the H-O bond is very prevalent (H-S to a lesser degree) on all proteins.
AD
primarysaqs
April 4, 2012 at 6:24 pm