PTCB - Chapter 10 - Basic Bio Pharmaceuticals - Definitions

Agonist
- drugs that activate receptors to accelerate or slow normal cellular function

Antagonist
- drugs that bind with receptors but do not activate them
- they block receptor action by preventing other drugs or substances from activating them

Receptor
- the cellular material located at the site of action that interacts with the drug

Selective (action)
- the characteristic of a drug that makes its action specific to certain receptors and tissues

Site of action
- the location where an administered drug produces an effort

Duration of action
- the time drug concentration is above the MEC

Minimum Effective Concentration (MEC)
- the blood concentration needed for a drug to produce a response

Minimum Toxic Concentration (MTC)
- the upper limit of the therapeutic windows
- drug concentrations above the MTC increase the risk of undesired effects

Onset of action
- the time MEC is reached and the response occurs

Therapeutic window
- a drug's blood concentration range between its MEC and MTC

Active transport
- the movement of drugs from an area of lower concentration to an area of higher concentration; cellular energy is required

Disposition
- a term sometimes used to refer to all of the ADME processes together

Elimination
- the processes of metabolism and excretion

Hydrophilic
- capable of associating with or absorbing water

Hydrophobic
- water repelling; cannot associate with water

Lipoidal
- fat like substance

Passive diffusion
- the movement of drugs from an area of higher concentration to lower concentration

ADME
- blood concentrations are the result of four simultaneously occurring processes
- absorption, distribution, metabolism, excretion

Absorption
- the movement of a drug from the dosage formulation to the blood

Gastric emptying time
- the time a drug will stay in the stomach before it is emptied into the small intestine

Complexation
- when different molecules associate or attach to each other

Protein binding
- the attachment of a drug molecule to a plasma or tissue protein, effectively making the drug inactive, but also keeping it within the body

Enterohepatic cycling
- the transfer of drugs and their metabolites from the liver to the bile in the gallbladder, then into the intestine, and then back into circulation

Enzyme
- a complex protein that catalyzes chemical reactions

Enzyme induction
- the increase in hepatic enzyme activity that results in reduced metabolism of drugs

First pass metabolism
- the substantial degradation of an orally administered drug caused by enzyme metabolism in the liver before the drug reaches the systemic circulation

Metabolite
- the substance resulting from the body's transformation of an administered drugs

Glomerular filtration
- the blood filtering process of the nephron

Nephron
- the functional unit of the kidney

Absolute bioavailability
- the bioavailability of a drug product compared to the same drug in a rapidly administered IV solution

Bioavailability
- the amount of an administered dose that reaches the general circulation and the rate at which this occurs

Relative bioavailability
- the bioavailability of a drug product compared to the same drug in any other dosage form than a rapidly administered IV solution

Bioequivalency
- the comparison of bioavailability between two dosage forms

Pharmaceutical alternative
- drug products that contain the same active ingredient, but not necessarily in the same salt form, amount, or dosage form

Pharmaceutical equivalent
- drug products that contain identical amounts of the same active ingredient in the same dosage form

Therapeutic equivalent
- pharmaceutical equivalents that produce the same effects in patients