unit 1 Flashcards
pharmacology
the study of functional and biochemical aspects of drug action
neuropharmacology
the study of the effects of drug action on the nervous system
psychopharmacology
the study of behavioral and cognitive aspects of drug action
drug
any small molecule that when introduced into the body alters the body’s function by interacting at the molecular lebel
drug action
specific molecular changes produced by a drug when it binds to a receptor
drug effects
alterations in physiological and psychological functions
pharmacokinetics
the investigation of absorption, distribution, metabolism, and the elimination of drugs
pharmacodynamics
the mechanisms of action of drugs
toxicology
the toxic effects of drugs
dose of drug –> drug concentration in target organ over time
pharmocokinetics
drug concentration in target organ over time –> mechanism and magnitude of drug effect
pharmacodynamics
bioavailability
of the drug is the level of drug in the circulation that is available to interact with receptors
sources of drugs
exogenous, endogenous, xenobiotics
drug receptors
receptors largely determine the quantitative relationship between the amount (dose or concentration) of the drug and the biological effect. receptors are responsible for selectivity of a drugs action.
classification of drugs
on the order of 50 to 60 drug groupings. typically authors of psychopharmacology texts describe 5 to 8 classes of drugs as psychoactive
classification of drugs that alter mood, behavior, and/or cognitive functions
(stimulants and convulsants), (neural depressant, sedative-hypnotic, and anxiolytics), (narcotic analgesics), (hallucinogens), (antidepressants), (antipsychotic)
stimulants and convulsants
cause neural and behavioral excitation
neural depressant, sedative-hypnotic, and anxiolytics
reduce neural excitability (epilepsy), produce drowsiness, sedation, and sleep, reduce anxiety symptoms
narcotic analgesics
relieve pain, cause sleep
hallucinogens
psychedelics or pscyhotogens
antidepressants
relieve depression
antipsychotic
treat psychosis
the drug development process
1) discovery and development
2) preclinical research
3) clinical research
4) FDA review
5) FDA post-market safety monitoring
typically researchers discover new drugs through:
- new insights into a disease process that allows researchers to design a product to stop or reverse the effect of the disease
- tests of molecular compounds to find possible beneficial effects against many diseases
- new technologies that provide new ways to target medical products to specific sites within the body or to manipulate genetic material
- at this stage in the process, thousands of compounds may be potential candidates for development of compounds look promising and call for further study
once researchers identify a promising compound, experiments gather information on:
- how is it absorbed, distributed, metabolized, and excreted
- its potential benefits and mechanisms of action
- the best dose
- the best route of administration
- side effects
- how it interacts with other drugs and treatments
- its effectiveness as compared with similar drugs
before testing a drug in people,
researchers must find out whether it has the potential to cause serious harm
preclinical research
in vitro and in vivo
clinical research
studies, or trials done in people
phase 1 of clinical research
20 to 100 healthy volunteers
phase 2 clinical research
patients up to several hundred people with the disease/condition studied for several months to 2 years to determine efficacy and side effects. only about 33% of drugs to move to the next phase
phase 3 clinical research
300 to 3,000 volunteers who have the disease or condition. the purpose is to establish efficacy and monitor for adverse reactions. can last for 1 to 4 years. percentage of drugs that move to the next phase is 25-30%
phase 4 clinical research
several thousand volunteers who have the disease/condition. the purpose is to obtain additional data on efficacy and side effects
FDA review
if early tests and preclinical and clinical research show that the drug is safe and effective the company can file an application to market the drug, the FDA thoroughly examines all submitted data and decided whether or not to approve the drug
for FDA review the company must provide information about
proposed labeling, safety updates, drug abuse information, patient information, any data from studies conducted outside the U.S, institutional review board compliance information, and directions for use
FDA post-market safety monitoring
the true picture of a product’s safety evolves over the time after it is put on the market. FDA reviews reports of problems and can decide to add cautions to the dosage or usage information, as well as other measure for more serious issues
thalidomide
in 1961, reports began to emerge associating the drug with severe birth defects. by march of 1962, the drug was banned in most countries where it was previously sold
teratology
the study of abnormalities of physiological development. abnormalities are often produced by drugs taken during pregnancy
teratogens
substances that may cause birth defects via a toxic effect on an embryo or fetus
teratological testing
a key area of pharmacological toxicology necessary to gain FDA approval of a drug
chemical name
the scientific name that is based on the molecular structure of the drug
generic or proprietary name
during drug development companies apply to regulatory agencies for a generic or nonproprietary name
antidepressants
a drug class that contains medications used to treat major depressive disorder, some anxiety disorders, some chronic pain conditions, and help to manage some addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, headaches, sexual dysfunction, and emotional blunting
anxiolytic
a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiety disorders and their related psychological and physical symptoms.
Anxiety, mild behavioral agitation, and insomnia.
bioavailability
the proportion of a drug or other substance which enters the circulation when introduced into the body and so is able to have an active effect.
Key indicator of drug absorption. It represents the administered dose fraction which archives success in reaching the systemic circulation when administered orally or through any other extravascular dosing route.
clearance
is equal to the rate at which a drug is removed from plasma (mg/min) divided by the concentration of that drug in the plasma. The total ability of the body to clear the drug from the plasma is renal clearance plus hepatic clearance plus clearance from all other tissues.
clinical response
also used as an indicator of therapeutic efficacy in combination with other indicators. Represents a complex phenotypes that emerges from the interplay of drug-specific, human body, and environmental factors
convulsants
a drug which induces convulsions and/or epileptic seizures. These drugs generally act as stimulants at low doses.
Substances that act in the brain stem or spinal cord to produce tonic or clonic convulsions, often by removing normal inhibitory tone. They were formerly used to stimulate respiration or as antidotes to barbiturate overdose
distribution
the movement of a drug to and from the blood and various tissues of the body and the relative proportions of drugs in the tissue
Distribution is generally uneven because of differences in blood perfusion, tissue binging (because of lipid content), regional pH, and permeability of cell membranes
The entry rate of a drug into a tissue depends on the rate of blood flow to the tissue, tissue mass, and partition characteristics between blood and tissue.
The extent of drug distribution into tissues depends on the degree of plasma protein and tissue binding. In the bloodstream, drugs are transported partly in solution as free drug and partly reversibly bound to blood components.
efficacy
describes the maximum response that can be achieved with a drug. The effect of the drug is plotted against dose in a graph, to give the dose-response curve. The increasing doses are displayed by the X acis and the half maximal and maximal responses are displayed by the Y axis.
hallucinogens
large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by altered states of consciousness characterized by major alterations in thought, mood, and perception, among other changes. Most hallucinogens can be categorized as psychedelics, dissociatives, or delirants.
narcotic analgesics
substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief.
Have actions at two sites, the presynaptic nerve terminal and the postsynaptic neuron. The postsynaptic actions of opioids are usually inhibitory. The presynaptic action of opioids is to inhibit neurotransmitter release, and this is considered to be their major effect in the nervous system.
