Psychopharmacology Flashcards
Psychopharmacology
A field interested in studying the effects of drugs on the nervous system and behaviors
Drug
an exogenous chemical not necessary for normal cellular function that significantly alters the functions of the certain cells of the body when taken in relatively low doses
pharmacokinetics
studies how drugs move through the entire body and process the chemicals
Pharmacodynamics
studies how drugs change the body
What does pharmacodynamics cover?
Absorption, distribution, metabolism, and excretion
oral administration
most common, broken down by stomach acid, some drugs destroyed this way (insulin)
Sublingual administration
placed under tongue and dissolved, absorbed by capillaries that supply mucous membrane of mouth
intrarectal administration
into rectum, most common for drugs that upset the stomach
inhalation
vaporous substance into lungs; route from lungs to brain is short, so drugs have rapid effects
Topical administration
directly onto skin or through mucous membrane of nose
Subcutaneous injections
into space beneath skin, useful if small amount is needed
IV
directly into vein, fastest route. entire dose releases into bloodstream instantly.
Intraparietal injection
into the parietal cavity
Intramuscular injection
directly into a muscle
intracerebral injection
injected directly into brain. used when the med cant cross the BBB
Intracellular ventricular injection
into one of the cerebral ventricles; widespread distribution of a drug throughout brain.
What is the speed of absorption based on?
The route of administration and lipid solubility
Where are most drug cites of action located?
the central nervous system
Enzymes
deactivate drugs. proteins that act as a catalyst to accelerate chemical reactions, found primarily in the liver
what does pharmacodynamics cover?
drug effectiveness, reuptake or destruction of NT’s, production, storage, and ligand and receptor binding
Dose response curves
a graph of the magnitude of the drug effect based on the amount of the drug
Why does drug effectiveness vary?
drugs vary in their affinity, with their sites of action. placebo effect , repeated administration
Drug affinity
the extent to which a drug binds to receptors
Placebo
an innocuous substance with no specific effect
Nocebo
negative expectations lead to a negative outcome
Tolerance
decreases the effectiveness of the drug
sensitization
increases the effectiveness of the drug
compensatory mechanisms
decrease in the effectiveness of binding to receptors. (reduced affinity or fewer receptors) A process that couples the receptors to ion channels in the membrane or to the production of second messengers (the second messengers become less effective)
Agonists
facilitate postsynaptic effects
Antagonists
block or inhibit postsynaptic effects
The agonistic effect
binds with proteins and directly triggers the release of a NT (increases
The antagonistic effect
The drug blocks the transporter molecules from filling the synaptic vesicles. The vesicles remain empty and nothing is released. This prevents the release of a NT
A direct agonist
the drug mimics the effects of a neurotransmitter
A direct antagonist
the drug binds with the postsynaptic receptor, but does not open the ion channel
An indirect agonist
facilitates the opening of an ion channel
An indirect antagonist
prevents the ion channel from opening
Noncompetitive binding site
The drug binds to one site, but still allows another NT to bind to another site
