module 1: history of drug use and development Flashcards
definition of drug
a substance received by a biological system that is not received for nutritional purposes, influences the biological function of an organism
opium is contains which two substances
morphine (10%) and codeine (0.5%)
ephedrine is a derivative of what chinese drug and what does it treat
ma huang, treats asthma, used as a decongestant
how is curare used in modern times
as an anesthetic during surgery
what are the effects of the poison ergot
causes violent contractions of the uterus, can cause hallucinations, convulsions, constructions of blood vessels, cause limbs to fall off
when is ergotamine used
used to treat migraines by constricting blood vessels.
when is ergotovine used
used to hasten birth, can be used to arrest uterine bleeding after childbirth
what is the active ingredient in peyote that causes hallucinations
mescaline
what percent of drugs are derived from plant sources
25%
___ is similar is structure to ergotamine and ergotovine
LSD
when was LSD synthesized
1943 by albert hofman
invented in the 1900s, this drug selectively binds to parasites, lead to the cure for syphilis
organoarsenics
invented in 1930s, first successful synthetic antimicrobial
sulfa drugs
1940s, first antibiotic, used in second world war for gram positive bacterial diseases.
penicillin
invented in 1950s, treated TB and gram negative diseases.
streptomycin
bacteria with thick cell wall and no outer membrane ( diphtheria, staphylococcus)
gram positive
bacteria with thin cell wall and outer membrane (cholera, e. coli)
gram negative
the well established way to prove or disprove the value of a new medication or treated is a randomized controlled trial (RCT) this means that
the people who administer the drugs do not know who is receiving the new drug. or are double blind
The maximum pharmacological response that can be produced by a specific drug in that biological system
Efficacy
The dose of a drug that is required to produce a response of a certain magnitude, usually 50% of the maximal response for that drug. Refers only to the amount of drug that must be given to obtain a particular response.
Potency
What is the difference between efficacy and potency?
Efficacy refers to the drugs ability to effectively activate the receptor once it has bound to it. It tells how you effective a drug is at produced the desired effect. Potency is the amount of a drug that is necessary to produce a desired effect. Or how strong a drug is
The therapeutic range is best described as?
The range of blood concentration where the frugnis effective but toxicities usually do not occur
Processes involved in pharmacokinetics
ADME absorption distribution metabolism excretion
Routes of administration
Topical (skin, inhalation)
Enteral (mouth rectum sublingual and buccal)
Parenteral(IV IM subcutaneous)
Advantages of sublingual and buccal administration. Disadvantages
It bypasses enzymes of the stomach, intestines and liver. Not all drugs are adequately absorbed from this route
Advantages and disadvantages of mouth administration
Most commonly used to administer. Most convenient and least expensive. Non invasive.
Variable absorption between patients due to differences intestinal motility
Advantages and disadvantages of rectal administration
Can be used in patients who are nauseated or vomiting, less invasive route for comatose patients. Digestive enzymes of stomach are bypassed.
Only a number of medications of available for this route. Absorption from rectal mucosa slow incomplete and variable
Bioavailability
The amount of an administered dose that reaches the blood in an active form. Eg intravenous is 100% biolavailable. Any other route would be less
Most to least bioavailable route of administration
Parenteral, enteral, topical
Define absorption
The movement of a drug from the site of administration into the blood
Define distribution
The movement of a drug from the blood to the site of action and other tissues
Biotransformation or drug metabolism
Conversion of a drug to a different chemical compound in order to eliminate it.
To be eliminated from the body by the kidneys, a drug must be _____ _______
Water soluble
P450
Enzymes capable of biotransforming drugs. Found innmoet tissue but abundant in the liver
Phase 1 and 2 of biotransformation reaction
1: purpose is to add or unmask a functional group on the drug to prepare it for the addition of a large water-soluble molecule in the phase 2 reaction.
2: addition of a large water soluble moiety( glucaronic acid), making the betabolite water soluble to be excreted by kidneys
Therapeutic index
Td/Ed
Examples of drug- drug interactions
Absorption - drug can increase intestinal movement, speeding the passage of a second drug through the intestine and decreasing contact of the second drug with the intestinal wall, decreasing absorption.
Metabolism- drug can block the inactivation of a second drug in the liver. Increasing the blood level and pharmacologal effect of the second drug
Drug food interactions
Grapefruit
Tyramine
Neurotransmitters
Glutamate
Catecholmines
GABA
serotonin
Acetylcholine
Opiod peptide
What receptors does glutamate match with
Glutamatergic receptors
Norepinephrine receptors
Alpha and beta receptors
Acetylcholine receptors
Nicotinic and muscarinic receptors
GABA receptors
Gabaergic receptors
Primary excitatory neurotransmitter
Glutamate
drug development process 5 steps
basic research and drug discovery, preclinical trials, clinical trials. health canada review and manufacturing,
post market surveillance
