drug delivery systems Flashcards
what are the type of drug deliveries
oral, injection based, transdermal and carrier based
what determines the drug delivery system we use?
dose of the drug given
frequency of administration
timing of administration
what factors have to be considering when choosing a dosage regime
impared functions
age and weight
disease to be treated
drug toxicity
when is suspenisions used
drugs which are insoluble unplayable as they are better tolerated
what are the advantages to tablets and capsules
Convenience Accuracy of dose Reproducibility Drug stability Ease of mass production
what is the purpose of enteric coated tablets
Protect the drug from stomach acid
Omeprazole
Protect the stomach from the drug
Aspirin
what does enteric coating delay?
disintergration of the tablet until it reaches the small intestine
why are prolongued or delayed release formulations useful ?
Most disorders required prolonged therapy
Maintains drug levels within a therapeutic range
Reduces the need for frequent dosing
Compliance is improved
Improved nursing and doctor compliance
what are advantages of prodrugs
prolongation of duration of action
avoidance of degradation of the drug in the gut
when would you use buccal and sublingual administration
for drugs which have extensive pre-systemic or first pass metabolism
when would you use rectal route
young or old, patients unable to swallow
why is injection based drug delivery system
fast systemic effects bypassing first-metabolism
when are drug given intravenously
a rapid onset of action is required
careful control of plasma levels is required
a drug has a short half-life
IV formulations may be given when
rapidly
slowly to prevent toxic effects
how does transdermal drug delivery system work?
The drug crosses the skin surface by diffusion by percutaneous absorption and goes into systemic circulation
