Principles of Pharmacology Guide | Galen (Latest
2026/ 2027 Update) 100% Verified Questions &
Answers | Grade A
Q: Pharmacokinetics
Answer
The process in which medications move through the body
Q: What are the 4 phases of pharmacokinetics?
Answer
absorption, distribution, metabolism, excretion
Q: Absorption
Answer
happens with drug movement from the GI tract into the bloodstream. Most meds are taken by
mouth.
Q: Oral absorption
Answer
Takes awhile to get absorbed because it has to go through the GI system
,Q: Usually takes 2-4 hours
Answer
•Enteric coated
aspirin - hard on stomach
can not crush pill
•Extended release
absorbed in the small intestine
Q: IM absorption
Answer
Absorbed 1-2 hours
Q: IV absorption
Answer
Absorbed 30-60 minutes
Q: dissolution
Answer
Dissolution happens when a po medication breaks down into particles, disintegrates, and
dissolves to combine with liquid so absorption from the GI tract into the bloodstream occurs.
Liquid medications are absorbed faster than solids. Food can interfere with the absorption of
drugs.
,Q: Drugs that resist dissolution
Answer
Parenteral medications (SL, eyedrops, inhalants, transdermal) do not pass through the GI tract.
Enteric coated medications are designed to resist disintegration until the pill reaches the small
intestine. EC and sustained release meds should not be crushed.
Q: Factors that affect absorption
Answer
•Lack of muscle and increased fat changes medicine absorption
•Food consumption - will change medicine potency (delayed)
•Stress - Exercise, medicine goes to muscle
•pH - Medicine is made for acidic environments
•Antacid changes absorption
•Taken alone so it doesn't change the action
Q: Excipients
Answer
Fillers and other substances that make up tablets as a pill is not 100% drug.
Sometimes an excipient enhances the absorption of a drug such as with PCN, which is not well
absorbed from the GI tract.
Adding Na to PCN, which makes it penicillin sodium, will increase the absorption of PCN
Q: first pass effect
Answer
•the oral drugs go to liver via portal vein where some of the drug becomes inactive
, •Only happens with oral medications
Q: delayed gastric emptying
Answer
Food doesn't move like it should
Q: Distribution
Answer
refers to the movement of the drug from the circulation to body tissues
Q: Factors affecting distribution
Answer
-blood flow to tissues
-protein binding
-blood brain barrier
-drug's affinity to the tissue
Q: protein binding
Answer
Drugs bind with proteins in blood
Some drugs are highly protein bound and other are weakly protein bound