Introduction to Pharmacology Flashcards
From which plant is the drug atropine derived?
Atropa belladonna (deadly nightshade)
What physiological effects are caused by atropine?
Pupil dilation
Increased heart rate
Dry mouth
Blocks muscarinic acetylcholine receptors (parasympathetic nervous system)
What is the definition of pharmacokinetics
The way that the body affects the drug
What is the definition of pharmacodynamics
The way that the drug affects the body
What method of administration gives the fastest response
Intravenous
For a drug to pass through a membrane by diffusion, what must it be
Lipophilic
What is meant by the term ‘first pass metabolism’
Substances absorbed from the stomach and intestines are transported to the liver via the hepatic portal vein. As they pass through the liver, they can be metabolised. The amount that enters the systemic circulation is known as bioavailability. It can be between 0-100%
What is the role of plasma proteins
To bind to lipophilic drugs so they can be transported in the blood
What is the name of the group of enzymes which catalyse phase 1 oxidation reactions in metabolism
Cytochrome P450 enzymes
What effect does conjugation (phase 2 reactions) have on the drug/ metabolite
Makes them less toxic and hydrophilic
Most drugs are eliminated via which route
Kidney (urine)
If a drug has a large therapeutic window, is it more or less safe to use
More
Why are some drugs taken once a day and others are taken 4 times a day
It depends on how fast the drug is metabolised (half life of the drug), and need to maintain the dose within the therapeutic window
What is a Endogenous ligand
Naturally occurring chemical
What is an Agonist
A drug which binds to a receptor and activates it, mimicking the endogenous transmitter
