Biopharmaceutics Flashcards
What is the difference between different dosage forms?
Different forms but both elicit the same response, regard,Ed’s of the mass of API in the drug
Define biopharmaceutics
How the chemical and physical properties of a drug, formulation and its administration route influence the rate of extent of drug absorption
Give examples of chemical and physical properties
Chemical - Polarity, water solubility
Physical - Whether it’s crystalline/amorphous, particle size
What is a formulation?
The dosage form and the excipients
Describe what process occurs to achieve a plasma concentration-time curve
Give drug at 0 mins, take blood of patient, extract the plasma via centrifugal ion to find the conc of drug in the drug
Describe a plasma conc-time curve
Plasma conc against time after drug administration
Absorption occurs hence steep incline reaching the Cmax
Curve starts to decrease gradually due to excretion of the drug over time
What is the Cmax?
The most exposure at Tmax
What is the therapeutic window?
Where the plasma conc should lie, between the min effect concentration and the maximum safe concentration
What is the minimum effective concentration?
The minimum conc at which the drug starts to work = Onset time
What is the maximum safe concentration?
The maximum conc the drug should reach, above this will cause toxicity
What does the area under the curve represent?
Total exposure to drug, Ed a sufficient drug in the system for an effect (width of curve)
Describe the difference between a wide and narrow therapeutic window
Wide (good) - Large diff btw min/max threshold so handles variable absorption/any deviation in plasma conc
Narrow - Small diff btw min/max so need tight control of drug plasma conc
What dosage form would be best for a narrow therapeutic window?
IV solution for tightly controlled, precise dosing
