PCTH 201 Lecture Notes - Lecture 3: Warfarin, Point Mutation, Sodium Bicarbonate

• School: UBC
• Department: Pharmacology and Therapeutics
• Course: PCTH 201
• Professor: Andrew Horne

Document Summary

Pharmacokinetics (what does the body do to drugs?) Distribution: where the drug goes in the body. The movement of drug from the site of administration into the blood: by passive diffusion for most drugs. Influencing factors: concentration gradient (high low, drug size (<1 kda, lipid solubility / ph. Weak acids and bases: most drugs are the salts of weak acids or bases. Exist in equilibrium between protonated & unprotonated forms. Weak acid: ha h+ + a- Absorption effect of charge: only the uncharged (un-ionized) form will passively diffuse across membranes. The drug does not know where to go in the body. Encounters receptors for which it has affinity. When it binds, a pharmacological response is triggered. The process by which drug reversibly leaves the bloodstream: drug moves between body compartments, drug reaches the site of action (receptors) Influencing factors: concentration gradient, drug size, lipid solubility / ph, blood flow, protein binding.