Flashcards in Basics Deck (38)
The branch of medicine concerned with the uses, effects and modes of action of drugs is called what?
Pharmacology (toxicology is concerned with dosages)
How the body acts on a drug is called what?
How the drug acts on the body is called what?
Pharmacodynamics (usually receptors)
What is an agonist?
Drug or natural ligand that activates the receptor. Sometimes selective, sometimes not
What does an antagonist do?
Interferes with agonist by binding to the receptor without activating it. Typically shifts dose-response curve to the right. Often competitive
What does an allosteric activator do?
Binds receptor at a separate site from the agonist and potentiates its effect
What does an allosteric inhibitor do?
Binds receptor at a separate site from the agonist to decrease its affect. Non competitive and often reversible
Rank the types of agonists from greatest to leasts response
Full agonist > Partial agonist > Antagonist > inverse agonist
The effective concentration for 50% of the total response is called what?
The concentration required to bind 50% of receptors is called what?
Competitive inhibition affects the _________ for a max response while non-competitive inhibition affects the __________
concentration, max response
The greatest effect a drug can elicit is called the ________ while the beginning of an effect is called the ________
What are 3 types of drug-receptor interactions?
What are two additional forms of antagonists?
-Chemical (does not involve receptor)
-Physiological (involves regulatory pathways with different receptors)
The number of receptors required to reach maximum response is called?
The relative concentration of two or more drugs to produce the same drug effect is called what?
How is therapeutic index calculated?
Toxic dose/Therapeutic dose= Therapeutic index
*bigger number means there is a bigger window of dosage. Also true of margin of safety
What are the 3 main ways to administer drugs parenteral? (not by way of intestine or G.I. tract)
1-Intravenous (very fast)
2-Intramuscular (prompt absorption, large volume possible)
3-Subtunaeous (adsorption less rapid, smaller volume)
What are the 3 main ways to administer drugs enterally? (by way of intestine or G.I. tract)
1-Buccal or sublingual (fast absorption)
2-Oral (most common and convenient, 30 minutes till effect)
3-Rectal (less absorption, alternative to other administration options)
What are 3 other ways to administer drugs other than parenteral and enteral?
1-Inhalation (very fast, within 5 minutes)
2-Topical (apply to a surface)
3-Transdermal (15 min onset, slow and sustained release)
A substance that brings about a change in biologic function through chemical actions is a?
The subset of drugs used for therapeutic benefit are called?
Chemicals not synthesized in the body are called?
What are 4 factors that affect absorption?
1-Route of administration
4-Cell membrane characteristics
What two chemical properties of drugs are very important for absorption?
-Lipid soluble or water soluble
-Size of molecule (small go more places)
What are two things that affect the bioavailability of a drug?
1-dissolving of drug by GI tract
2-destruction of drug by liver
*intravenous administration results in 100% bioavailability
The apparent space in the body available to contain a drug calculated through volume distribution using what equation?
Volume of Distribution=Amount of drug in body/Concentration of drug
What equation is used to determine half-life using Volume of distribution?
The rate of process of elimination of a drug is measure by clearance using what equation?
Clearance= Rate of elimination/Concentration of the drug