Pharmacology Flashcards
Pharmacokinetics
The study of drug absorption, distribution, metabolism, and excretion (ADME). This is what the body does to the drug.
ADME
Absorption
Distribution
Metabolism
Excretion
True or False: ADME can be affected by factors like age, race, gender, genetics.
True
True or False: ADME can be affected by factors like dosage form, foods, disease contains, and simultaneous usage of other drugs.
True
Drug absorption
The transfer of drugs into the bloodstream
3 factors that affect drug absorption:
Gastric emptying time
Bile salts and enzymes
Intestinal movement
4 factors that affect gastric emptying time
Amount and type of food in stomach
Other drugs
Emotional state
Body position
If a drug stays in the stomach for a long time is it more or less likely to be absorbed?
Less likely
Will slow intestinal movement result in lesser or greater drug absorption
Greater absorption
Why does a longer gastric emptying time result in less absorption?
The longer a drug stays in the stomach the more likely it will be destroyed by stomach acids instead of entering into the bloodstream
Why does slower intestinal movement result in greater drug absorption?
The longer a drug is in contact with the intestinal membrane, the more it will be absorbed.
What role do bile salts play in absorption?
Bile salts in the intestinal tract increase the absorption of hydrophilic drugs.
What role do enzymes play in absorption?
Enzymes can destroy drugs and reduce absorption
The half-life of a drug
The time it takes for the blood concentration of a drug to reduce by half.
Drug distribution
The transfer of drugs between the bloodstream and various body tissues/membranes
3 factors that affect drug distribution
Blood flow rate
Tissue membrane permeability
Protein bindings
How does blood flow rate affect distribution?
Drugs are distributed quicker to organs with high flow rate.
2 organs with high flow rate
Heart
Liver
2 organs with low flow rate
Skin
Muscle
True or False: Most tissue membranes are highly permeable
True
True or False: The blood-brain barrier is a highly permeable membrane
False
What role does protein binding play in drug distribution?
Some drugs may bind to proteins in the blood plasma, preventing the drug from passing through the tissue membrane
Drug metabolism
The breakdown of drugs into compounds that can be excreted