General Flashcards
Define therapeutic range
The ideal plasma concentration between minimal effective concentration and minimum toxic concentration
List 8 ways drugs can enter the body
- Oral
- IV
- Topical
- Sublingual
- Inhalation
- Rectal
- Intramuscular (eg vaccines)
- Subcutaneous
Oral drug administration is also called:
Enteric
What are three important factors to consider for drugs to cross the membrane (in the intestine for absorption)
- Size
- Lipid solubility
- Transporter availability
In order to cross a membrane passively, drugs need to be charged or uncharged
NOT charged
Ie if they are a weak acid they have their H atom.
When is IV drug administration used?
- Drugs that are poorly absorbed in the GI tract
- Rapid effect (bolus delivery)
NO METABOLISM before entering the blood stream
What is bioavailability?
The proportion of a drug administered which reaches the blood stream
List 4 things which can alter absorption of drugs
- Gut transit time eg vomiting or diahorea
- Blood flow
- Other medications
- Genetic and microbial diversity
Why do the lungs, heart, brain, liver and kidney receive drugs faster than muscles, fat, skin and bone?
Better blood supply
What is ‘volume of distribution’ in drugs
The volume throughout which a drug is distributed and therefore its concentration.
Some drugs eg warfarin are in plasma only, whilst some are highly lipid soluble and bind to proteins so have a large VD - eg penicillin
List the 4 key features which affect how much drug reaches the bloodstream and tissues
- Administration route
- Charge
- Bioavailability
- Distribution
5 factors which affect drug metabolism
- Age
- Race
- Body composition
- Diet
- Genetics
Drugs are mostly excreted in:
Urine
What is half life?
Time for plasma concentration of drug to halve
What is drug efficacy?
Maximal response a drug can produce
