Unit 3 Pharm Guiding Questions Flashcards
What is the blood brain barrier?
refers to the unique structure and function of CNS capillaries, which act as a selective filter and protects the CNS by limiting the substances that enter the brain and spinal cord
What is the blood brain barrier’s role in clinical pharmacotherapeutics?
-nonpolar, lipid-soluble drugs are able to cross the barrier by passive diffusion
-polar and lipophobic compounds are usually unable to enter the brain but exceptions occur because of the presence of carrier-mediated transport systems
central neurotransmitters that have an excitation effect
-acetylcholine
-glutamate, aspartate
-substance P
-enkephalins
central neurotransmitters that have an inhibition effect
-norepinephrine
-dopamine
-serotonin
-GABA
-glycine
the majority of CNS drugs work by modifying synaptic transmission in some way.
list the sites at which drugs can alter transmission at a CNS synapse.
- action potential
- synthesis
- storage
- release
- reuptake
- degradation
- postsynaptic receptor
- presynaptic “autoreceptor”
- membrane
drugs that attempt to rectify CNS-related disorder do so by either ___ or ___ transmission at specific synapses.
increasing or decreasing
a drug that modifies synaptic transmutation must somehow alter the ___ of the neurotransmitter that is released from the presynaptic terminal or affect the ___ of postsynaptic receptors, or both.
quantity, stimulation
Why are barbiturates effective sedative hypnotics?
because of their specificity for neurons in the midbrain portion of the reticular formation as well as some limbic system structures
how to nonbenzodiazepine sedative hypnotics work?
they bind to the GABA receptors in the brain which causes GABA to bind more effectively thus increasing chloride conductance and the level of inhibition in the neuron. increased inhibition results in less arousal and promotion of sleep.
how do nonbenzodiazepines work?
they promote relaxation and sleep via depressing the CNS
pharmacokinetics of benzodiazepines and nonbenzodiazepine sedative hypnotics
usually highly lipid soluble
administered orally and absorbed easily from the GI tract
metabolized primarily by the liver
excretion occurs through the kidney after metabolism in the liver
pharmacokinetics of benzodiazepines and nonbenzodiazepine sedative hypnotics
usually highly lipid soluble
administered orally and absorbed easily from the GI tract
metabolized primarily by the liver
excretion occurs through the kidney after metabolism in the liver
what is the primary problem associated with sedative hypnotic use
residual effects that occur the day after (drowsiness and decreased motor performance)
define drug tolerance
the need to take more of a drug to exert the same effect
define drug dependence
the onset of withdrawal symptoms if drug administration is ceased
what are some other side effects of sedative hypnotics?
GI discomfort, dry mouth, sore throat, and muscular incoordination
cardiovascular and respiratory depression
primary drugs used to treat many forms of anxiety
benzodiazepines
pros and cons of buspirone
pros: produces less sedation and psychomotor impairment, smaller risk of developing tolerance and dependence
cons: may not take effect as quickly in patients with severe anxiety
most common side effect of anxiolytic benzodiazepines
sedation
problems and side effects associated with buspirone
dizziness, headache, nausea, and restlessness
when would it be beneficial to schedule a patient if they are on anxiolytic benzodiazepines
2-4 hours after oral administration (peak blood levels) may improve participation in treatment
examples of nonpharmacological interventions that may help decrease anxiety and improve sleep
regular exercise, massage, relaxation techniques, yoga, and other complementary therapies
affective disorder
innappropriate disposition, feeling unreasonably sad and discouraged, or fluctuating between periods of depression and excessive excitation and elation
the drugs that are currently used to treat depression are grouped into several categories, according to chemical or functional criteria:
selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, tricyclics, monoamine oxidase inhibitors, other compounds
most common side effects associated with SSRIs and SNRIs
GI symptoms such as nausea, vomiting, and diarrhea or constipation
may cause serious and fatal adverse effect - serotonin syndrome
serotonin syndrome
characterized by array of symptoms such as sweating, agitation, restlessness, shivering, increased heart rate and neuromuscular hyperexcitability
major problem with the tricyclic antidepressant
sedation
2nd - anticholinergic properties: dry mouth, constipation, urinary retention, confusion, and tachycardia
side effects of MAO inhibitors
CNS excitation: restlessness, irritability, agitation, and sleep loss
major problem with lithium
danger of accumulation within the body
not metabolized elimination takes place exclusively through excretion in the urine
