Routes of administration Flashcards
What is pharmacokinetics?
What the body does to the drug/ the relationship between drug administration and exposure to the drug
What is exposure?
It takes into account the concentration of drug that the patient sees as well as the time they see it for
Define what route of administration is?
It is the site through which the drug is administered/it should allow access to the desired site of action
What are the three classes of routes of administration?
- Enteral
- Parenteral
- Topical
Describe the three classes of routes of administration?
Enteral - via GI tract
Parenteral - via non GI tract route
Topical - Local administration/ does not allow drug to enter systemic circulation
What are the factors that affect exposure?
- Route of administration
- Frequency of dose of drug given
- Formulation of drug
- Genetic makeup of individual
What are the factors that affect choice of route?
- Goal - deliver to site of action
- Therapeutic consideration
- Effect of disease on route
- Drug properties
- Adverse events
- Patient preference
When a drug is administered topically, very small doses are required. TRUE OF FALSE? Give reason why?
TRUE - because drug is being administered directly to site of action
What is percutaneous route of administration?
This means administration through the skin e.g Parenteral (IV,IM)
What is Epicutaneous route of administration, and provide example?
This means applied to the surface of the skin e.g local anaesthetics/ inhalation/ Vaginal /Ocular
Provide some of the ads and disads of enteral route of administration?
Ads - convenient for patient and patient compliance
Disads - Drug must survive gastric acid / absorbed from small intestines /absorption relatively slow / first pass effect
What are the routes taken when a drug passes through first pass effect?
- Absorbed by small intestine
- Enters portal vein
- Passes through liver
- Exits via Hepatic vein
- Into the vena cava
- To the heart
- To the systemic circulation
Most drugs are absorbed in the small intestine. TRUE OR FALSE?
TRUE
Some drugs may not be soluble in acidic conditions TRUE OR FALSE?
TRUE
When patients takes drug with food, this can some times delay the rate of absorption of drug in small intestine. TRUE OF FALSE?
TRUE
