Group 1 - Pharmacology Terms and Definitions by StevenWal

Pka

2018-02-23 02:06:31 UTC

The pH that is 50% ionised and 50% unionised

Bioavailability

jade_g_khoury — 2018-02-23 02:07:07 UTC

The rate and extent of absorption of drugs reaching the systemic circulation via any route i.e oral, IV

Pharmacokinetics

2018-02-23 02:07:38 UTC

What the body does to the drug

Pharmacodynamics

2018-02-23 02:07:55 UTC

The effects of the drug on the body

Anaphylaxis

2018-02-23 02:08:09 UTC

Severe adverse allergic reaction that has a rapid onset affect on the body. Does not discriminate between sexes or ages

Cytochrome P450

2018-02-23 02:08:15 UTC

Family of isozymes responsible for the biotransformation of several drugs.

Elimination

2018-02-23 02:08:15 UTC

Hepatic first pass metabolism
Irreversible loss of the drug from the body

Pharmacodymanics

2018-02-23 02:08:38 UTC

The effect of a drug on the body: action-effect sequence + dose effect relationship. Also includes how one drug may modify the actions of another.
There are 5 basic types of drug action
1. Stimulation
2. Depression
3. Irritation
4. Replacement
5. Cytotoxic Action

Agonist

2018-02-23 02:08:43 UTC

A substance which initiates a physiological response when combined with a receptor

Lipid soluble

2018-02-23 02:08:48 UTC

Ability to penetrate the cell membrane - like fat

Volume of Distribution

jade_g_khoury — 2018-02-23 02:09:27 UTC

A body compartment into which a drug MIGHT be distributed e.g low Vd. (<5L) implies a drug is retained within vasculature + high Vd (>15L) drug is more lipid soluble & distributed to many parts of body compartments

Water soluble

2018-02-23 02:10:01 UTC

The ability to penetrate aqueous structures

Agonist

2018-02-23 02:10:45 UTC

Binding to a receptor and having a physiological response

Enterohepatic shunting

2018-02-23 02:10:48 UTC

A considerable number of drugs are excreted from liver into bile and from bile into small intestines.

Volume of Distribution

2018-02-23 02:10:50 UTC

the volume of distribution (V_D) is the theoretical volume that would be necessary to contain the total amount of an administered drug at the same concentration that it is observed in the blood plasma

Ionised and unionised drugs

2018-02-23 02:11:21 UTC

Antagonist

2018-02-23 02:12:02 UTC

Bringing to a receptor and not creating a physiological response

Pharmacodynamic

2018-02-23 02:13:18 UTC

Physiological and biochemical effects of a drug + their mechanism of action at organ/system/subcellular/macromolecular levels

Pharmacokinetic

2018-02-23 02:14:40 UTC

Movement of the drug in and alteration of the drug by the body. Often expressed as ADME
Absorption
Distribution
Metabolism
Excretion

Clearance

jade_g_khoury — 2018-02-23 02:14:45 UTC

Measurement of Vol. of Plasma from which substance is completely removed per unit time. (mL/min)

Half Life

jade_g_khoury — 2018-02-23 02:18:02 UTC

Amount of time taken for a drug to 1/2 relative to its initial concentration

Drug Selectivity

2018-02-23 02:19:22 UTC

Selectivity refers to a drug's ability to preferentially produce a particular effeDct and is related to the structural specificity of drug binding to receptors.

Ionisation

2018-02-23 02:19:58 UTC

Molecules with a positive charge, attracting water molecules forming a macro-complex. Cannot cross the membrane due to low lipid solubility

Drug Selectivity

2018-02-23 02:20:05 UTC

A property of a drug determined by combining its affinity at various binding sites, the knowledge of which can help predict a drug's potential for therapeutic and side effects.

2018-02-23 02:20:23 UTC

Tachyphylaxis

2018-02-23 02:22:24 UTC

Rapid desensitisation of the body to the drug - occurs in minutes usually

Metabolism

jade_g_khoury — 2018-02-23 02:25:16 UTC

Involves enzymes changing the molecular structure of a drug 2 important ways:
1. Drug made more water soluble = easier to excrete
2. Metabolites = less pharmacologically active

Protein Binding

2018-02-23 02:25:41 UTC

A drug’s efficiency may be affected by how it binds to the plasma proteins.
Common blood proteins that drugs bind to, are human serum, lipoprotein, α, β & γ globulins and albumin.

Zero Order Kinetics

2018-02-23 02:26:09 UTC

A constant proportion of drug is eliminated per unit time eg. alcohol

Drug Specificity

jade_g_khoury — 2018-02-23 02:27:12 UTC

The quality of a drug having a certain action, affecting certain organisms/tissue or reacting with only certain substances.

2018-02-23 02:27:39 UTC

Bioavailability

2018-02-23 02:27:47 UTC

The percentage of total concentration of a drug, that reaches the blood stream in tact

Competitive Antagonist

2018-02-23 02:28:09 UTC

Is a receptor antagonist that binds to a receptor but does not activate the receptor.

pH scale

2018-02-23 02:28:44 UTC

<7 Acidic (the lower the number the more acidic)
>7 Alkaline/Basic (the higher the number the more alkaline)
7 Neutral

Partial agonist

2018-02-23 02:31:35 UTC

Binds to a receptor but only has a partial efficacy

Partial Antagonist

2018-02-23 02:31:48 UTC

Are drugs that bind to and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist.

Competitive Antagonist

jade_g_khoury — 2018-02-23 02:31:54 UTC

Bind to receptors (active site) at the same binding site as the endogenous ligand or agonist but without activating the receptor, therefore once it binds it blocks agonist from binding.

Non-Competitive Antagonist

jade_g_khoury — 2018-02-23 02:33:29 UTC

Binds to an allosteric (non-agonist site) on the receptor to prevent activation of the receptor.

Cation

2018-02-23 02:39:41 UTC

- Positively charged ion

Anion
- Negatively charged ion

Inverse agonist

2018-02-23 02:41:08 UTC

Binding to the receptor and producing the opposite effect to the normal physiological response

Drug Tolerance

2018-02-23 02:41:09 UTC

- concept describing subjects' reduced reaction to a drug following its repeated use. Increasing its dosage may re-amplify the drug's effects, but this may accelerate tolerance, further reducing the drug's effects.
- Is indicative of drug use but is not necessarily associated with drug dependence or addiction.

Hepatic first pass effect

2018-02-23 02:41:26 UTC

First pass through the liver greatly reduces drug bioavailability before reaching to systemic circulation

ED-50 Pharmacology

jade_g_khoury — 2018-02-23 02:42:43 UTC

The median effective dose. The dosage required to achieve 50% of the desired response in 50% of the population

TD-50 Pharmacology

jade_g_khoury — 2018-02-23 02:44:03 UTC

Median toxic dose. The dose required to get 50% of the population reporting this specific toxic effect.

Pharmacotherapeutics

2018-02-23 02:44:08 UTC

The study of the therapeutics uses and effects of drugs; the study of beneficial and adverse effects of drugs

LD-50 Pharmacology

jade_g_khoury — 2018-02-23 02:45:28 UTC

The median lethal dose. The amount of toxic agent sufficient to kill 50% of a population within a certain time. e.g rat poison

Drug- Receptor Affinity

2018-02-23 02:54:30 UTC

How well a drug can bind to a receptor