Psychopharmacology Flashcards
Psychopharmacology
Study of how drugs affect the nervous system and behavior
Psychoactive drug
Substance that acts to alter mood, thought, or behavior
What route of administration is the safest, easiest, and most common
Oral administration
Which route of administration is the fastest and encounters the least barriers?
Injection directly into the brain
What molecules are fat soluble and can freely pass the blood-brain barrier?
Small, uncharged molecules such as oxygen and carbon dioxide
How do larger, charged molecules pass the blood-brain barrier?
Active transport
Drugs are broken down by the
liver, kidneys, and intestines
Drug family involved in drug catabolism
cytochrome P450
Most psychoactive drugs exert their effects by influencing chemical reactions at
synapses
Agonists
enhance the effectiveness of a neurotransmitter
Antagonists
substance that blocks/decreases the effects of a neurotransmitter
Presynaptic events that can be modified by drugs
Transport, synthesis, storage, transmission, release, receptor response, reuptake, degradation
Postsynaptic events can be modified by
blocking or activation of receptors, regulation of the number of postsynaptic receptors, and modulation of intracellular signals
Inverse agonists
bind to receptor and initiated opposite effect of usual transmitter
Competitive ligands
bind to the same part of receptor molecule as endogenous ligand (ex. nicotine binding in the place where Ach would bind)
Noncompetitive ligands
drugs that bind to modulatory sites that are not part of the receptor complex that normally binds the transmitter
Binding affinity
the degree of chemical attraction between a ligand and a receptor
Efficacy
the ability of a bound ligand to activate the receptor
antagonists have low efficacy and agonists have high efficacy
Why is the low binding affinity of neurotransmitters useful for neural impulses?
They will bind to receptors for short periods and then dissociate to be degraded. This is useful for the passage of information because many neurotransmitters can bind to receptors within a short period of time to transmit as many impulses as possible
Do most drugs have a higher or lower binding affinity than neurotransmitters?
Higher
Therapeutic index
the separation between an effective dose and a toxic one
Benzodiazepines ______ binding affinity for GABA
enhance
T/F if there is no GABA present in the brain, benzodiazepines will still work. Why or why not?
false
Benzodiazepines only increase binding affinity for GABA, so if there is no GABA present, the binding affinity of GABA doesn’t matter
T/F long term alcohol abuse directly affects the brain
false- it directly affects the liver which in turn affects the brain
