Flashcards in Introduction to the Principles of Pharmacology Deck (15):
What is Pharmacology?
the science basic to medicine that is about the effects of chemicals on living systems at all levels of organization (molecular to the whole body)
How to drugs act?
they modify physiological processes, they do not create new process or effects
What is Pharmacokinetics?
deals with the absorption, distribution, biotransformation, and excretion of drugs
(body having actions on the drug)
What is Pharmacodynamics?
deals with the study of the biochemical and physiological effects of drugs and their mechanisms of action
(drug having effects on the body)
What is Toxicology?
an aspect of pharmacology that deals with the adverse effects of drugs and chemicals
What is Pharmacotherapeutics?
the use of drugs in the prevention and treatment of disease
(many drugs stimulate or depress biochemical or physiological function in human beings in a sufficiently reproducible manner to provide relief of symptoms, or, ideally, to alter favorably the course of disease)
What is the Therapeutic Window?
the dose range over which one drug effect predominates (within this dose range the drug may be termed selective)
If a drug resulted in one and only one effect, the drug would be termed _____.
A drug is selective when...
it is within the therapeutic window.
When can toxicity result?
may result if the dose range is exceeded
What are three general mechanisms of drug action?
- REPLACEMENT THERAPY (due to DEFICIENCY of some essential component of a normally functioning body)
- EXCESS ACTION (of some normal, or even essential, ingredient of the organism can promote physiological difficulties - appropriate treatment might be to use a CHEMICAL ANTAGONIST)
- PHYSIOCHEMICAL ENVIRONMENT (of a specific party of the body may be altered by a drug)
- used for deficiency
- can replace substance or inhibit the breakdown or uptake of an endogenous chemical
ex: selective serotonin reuptake inhibitors (SSRIs) decrease the degradation of the endogenous neurotransmitter serotonin blocking a selective transporter responsible for the uptake of serotonin in the neuronal synapse, resulting in an overall increase in the serotonin neurotransmitter
What might be proper treatment for excess action?
- use of a chemical antagonist
ex: gastric acidity producing heartburn --> appropriate therapy is the administration of antacids, which are essentially alkaline compounds, designed to neutralize the acid
- excess action may also result from activity of exogenous substances - in such cases, specific (i.e. receptors) antagonists may be called for
ex: herion overdose; use an opioid antagonist such as naloxone
*antagonist: a substance that interferes with or inhibits the physiological action of another
...of a specific part of the boy may be altered by a drug
ex: laxatives or antacids act by changing the characteristics of the GI tract allowing more water to accumulate in the lumen of the GI or neutralize the acid, respectively