principles of pharmacology Flashcards
what is pharmacology?
is the study of effect of drugs on living tissues
what are drugs?
chemicals that alter the physiological function of cells in a specific way
what is pharmacodynamics?
Pharmacodynamics is the study of the biochemical and physiologic effects of drugs (what the drug does to the body) .
its the relationship between the drug and the therapeutic response
how do drugs exert their effects?
Most drugs exert their effects by binding to specific target protein molecules.
name some targets that drugs bind to
These targets include:
- Classic receptors (e.g. muscarinic receptors)
- Enzymes
- Transmembrane transport proteins
- Ion channels
what is a agonist?
when a drug stimulates its target to produce a desired response
what is a antagonist?
when a drug blocks the target to prevent binding of the natural agonist
Antagonists can be competitive (competes with the naturally occurring agonist) or non-competitive
name the 3 sources of drugs
Natural e.g. alkaloids
Semi-synthetic: prepared by chemical modification of natural drugs
Synthetic: prepared by chemical synthesis in pharmaceutical laboratories
what is a ophthalmic example of a naturally derived drug and its side effect?
Atropine (derived from plants and is still used as a cycloplegia agent but have been replaced by synthetic drugs nowadays)
Side effect of atropine- its longer dilating and takes many days for effect of atropine to wear off
what is a ophthalmic example of a semi-synthetic drug and how is it better than a naturally derived drug?
Cyclopentolate - is produced by altering chemical structure of atropine to maintain its effect on the pupil but shorten its action
what is a ophthalmic example of a synthetic drug and what is it used for?
Latanoprost- most common drug for treating glaucoma
what is drug specificity?
how selectively a drug interacts with its intended target in the body. A drug is considered to have high specificity if it binds primarily to its intended target and triggers the desired therapeutic effect without affecting other biological systems and leading to fewer side effects.
However, absolute specificity is rare because even highly targeted drugs can sometimes interact with other targets in the body.
what does increasing the dose of a drug cause?
causes interaction with other unintended targets which can lead to side effects.
what does potency refer to? and what does a drug with lower potency need?
Potency refers to how much of a drug is needed to achieve a therapeutic effect.
Drugs with lower potency require a higher dose to reach the same therapeutic effect. However, with a higher dose comes an increased chance of unwanted off-target effects.
what will an overdose cause?
An overdose of a drug will likely cause significant side effects, as the drug will begin to affect many non-target systems in the body. This can lead to toxicity or harm.
what is the goal of drug therapy?
maximize the therapeutic response (desired effect) while keeping the dose low enough to minimize side effects.
