Drug Delivery Flashcards
What characteristics of the patient influence drug formulation?
- Patients Needs
- Their disease state
- Their pharmacological characteristics.
What 5 things are to be considered when determining dosage regime?
- Any renal/hepatic failure
- The recommended doses
- Age & weight
- Disease
- Drugs Toxicity
Where are oral meds absorbed into systemic circulation?
Oral meds absorped in the GI tract
Define a suspension:
Coarse drug particles in a liquid phase
What type of drugs are used in suspension?
Insoluble & unpalatable drugs
What type of patients would use solutoins/suspensions over tablets?
People with swallowing difficulties including the very young & old.
How are solution & suspensions delivered?
By naso-gastric or Peg tubes
What is the rate limitng step in tablet absorption?
The tablets break down or “dissolution”
What are the main advantages of tablet/capsule drugs?
- convenient to use
- accurate doses
- easily reproducible in mass
- high drug stability
Why would you use an enteric coating on a tablet?
Protect from destructive stomach acid (Allowing it to reach the small intestine) or protect stomach from a toxic drug
What drugs are enteric coated & why?
Omeprazole, to protect it from stomach acid
Aspirin to protect the stomach from it.
Why don’t enteric coated tablets disintegrate till they reach the small intestine?
Only disintegrate in higher pHs, stomach is very acidic so unchanged in it
What are the advantages o prodrugs?
Avoid drug degradation in gut
Prolong duration of action
What does a prolonged release formulation do?
Maintains drug level within therapeutic range over a longer period
How does using prolonged release formulations improve patient compliance?
Prolonged release formulations need less frequent doses, increasing odds a patient will take them all
In what 3 forms do prolonged release formulation geerally come?
Oral tablets
Intramuscular Injection
Surgical implants
What drugs are delivered by surgical implant?
Progesterone (contraception)
Testosterone
What drugs are ideal for buccal/sublingual administration?
large amount of pre-systemic or first pass metabolism
Do rectally delivered drugs treat locally or systemically?
both local & systemic conditions