Psychopharmacolgy - intro, monomamines, amino acids, cholinergics + antidepressants

what does an agonist do

helps neurotransmitter activity

what does an antagonist do

blocks neurotransmitter activity

what is akathesia

a movement disorder that is a common SE of psychoactive meds; caused by restlessness > usually affects the legs

what does approved use mean

what the med is approved by the FDA for

what is a black box warning

most serious warning a drug can come with and still be approved for use in humans

what does efficacy mean

the maximum therapeutic effect a med can achieve

what is a half life

length required for drug to decrease by 1/2 in the body

what does lipid solubility mean

the ability to pass across a cell membrane

with high lipid solubility there is...

a smaller therapeutic range; it is absorbed faster, making it easier to OD

what does off label mean

using the drug for something other than what it was approved for by the FDA

what is the rule of thumb for completely clearing a drug from the body

it will take ~ 5 1/2 lives

what does potency mean

amount of drug required to produce an effect

what does psychotropic mean

a medication that affects a person's mental state

what is the rebound affect

when symptoms come back when med d/c or reduced

what is reuptake

when a neuron reabsorbs up and recycles its own chemical signs

what is the therapeutic index (TI)

TI = LD50/ED50

when a person experiences respiratory depression what part of the brain is being affected by a CNS depressant

medulla oblongata

what is the purpose of psychoactive medications

manage problem behaviors and symptoms

what is the difference between neurotransmission vs synaptic transmission

neuro: conduction of electrical impulse from one end of neuron to the other

synaptic: handoff of one neuron to another

what is an inhibitory neurotransmitter

chemical in the brain that slows/stops neurons from firing

what is an excitatory neurotransmitter

a chemical in the brain that promotes neurons to fire

what monoamines are commonly affected by psychoactive meds

dopamine (DA), norepinephrine (NE), serotonin (5HT), histamine (H)

what amino acids are affected by psychoactive meds

γ-aminobutyric acid (GABA), and glutamate (NMDA/AMPA)

what cholinergics are affected by psychoactive meds

acetylcholine (Ach)

what peptides are affected by psychoactive meds

substance P (SP), somatostatin (SRIF), neurotensin NT)

dopamine is a monoamine that helps with

- fine muscle movement

- decision making

- release of hormones (thyroid, sex, adrenal)

- integration of emotion and thoughts

what is the mnemonic for what dopamine helps with

My Dog Hates Treats

M: muscles

D: decision making

H: hormones

T: thoughts

what happens if there is an excess of DA

schizophrenia, psychosis, mania

what happens if there is a DA deficiency

parkinson's, depression

what is psychosis

loss of touch from reality

norepinephrine (NE) is a monoamine that helps with

mood, attention, arousal (vigilance), SNS stimulation

what happens if there is an excess of NE

mania, anxiety, psychosis, heightened state of arousal

what happens if there is a deficiency of NE

depression, lowered state of arousal

serotonin is a monomamine that helps with

sleep regulation, hunger, mood, pain perception, libido, aggression, hormonal activity

with excess 5HT we can see

anxiety

with a deficiency in 5HT we can see

depression

histamine(H) is a monoamine that helps with

alertness, gastric secretion stimulation, and inflammation response

with excess H we can see

sleep disturbances, anxiety

with a deficiency in H we can see

sedation, lower seizure threshold

γ-aminobutyric acid (GABA) is an aminoacid that helps with

decreasing anxiety, decreases excitement, decreases aggression, anticonvulsant

with excess of GABA we can see

reduction of anxiety

with a deficiency of GABA we can see

mania, anxiety, psychosis

glutamate is an aminoacid that helps with

memory, emotions, cognition

with an excess in glutamate we can see

increased perception of pain, anxiety, restlessness

with a deficiency in glutamate we can see

low energy, difficulty concentrating, insomnia, psychosis

acetylcholine (Ach) is an anticholinergic that helps with

learning, memory, mood regulation, sexual and aggressive behavior, PNS stimulant

with an excess of Ach we can see

depression

with a deficiency of Ach we can see

alzheimer's, parkinson's, and huntington's chorea

what is huntington's chorea

genetic disorder with jerky movements, thinking problems, and mood changes

what are the 4 major categories of psychoactive meds

antidepressants, mood stabilizers, antipsychotics, anxiolytics

what are the 4 common classes of antidepressants

TCAs, MAOIs, SSRIs, SNRIs

what are the 2 common classes of mood stabilizers

lithium, anticonvulsants

what are the 2 common classes of antipsychotics

1st gen (typical) and 2nd gen (atypical)

what are the 4 common classes of anxiolytics

benzodiazapines, antihistamines, anticonvulsants, beta blockers

what is the 1st line of treatment for major depression commonly

antidepressant - SSRIs

what do antidepressants help treat

major depression, panic disorders, some anxiety disorders, bipolar depression, psychotic depression, some personality disorders

what is the expected outcome of antidepressants

mood improvement and decreased anxiety

what is the MOA of SSRIs

inhibit reuptake of serotonin making it available longer in the synapse

what are common SE of SSRIs

tremors, N/D, HA, insomnia, drowsiness, sexual dysfunction, bruxism, anxiety, agitation, dry mouth, hyponatremia

what SSRI is especially associated with bruxism

paroxetine

what is bruxism

teeth grinding

what are the top three SSRIs

fluoxetine, paroxetine, escitalopram

what are some SSRI pt teaching key points

- avoid alcohol and antihistamines

-take with food

-take in AM

-take as prescribed,

-do NOT d/c abruptly

- let physician know if suicidal thoughts increase

how long do SSRIs take to be effective, when do we get the full effect

1-3 weeks to start 2-3 months for max effect

why can a patient not take other meds that effect serotonin levels with an SSRI

can cause serotonin toxicity

what is an unexpected medication that patients need to be careful with while taking SSRIs to avoid causing serotonin toxicity

OTC cough/cold meds

if a pt were to d/c SSRIs abruptly what might they experience (discontinuation syndrome)

- anxiety

- insomnia

- HA

- flu like symptoms

- "brain zaps"

- nausea

SSRIs have a black box warning for and for who

increased risk of suicide, especially at start of med and especially in younger population

what does SHIVERS stand for regarding Serotonin Syndrome

S: shivering

H: hyperreflexia and myoclonus (rhabdomyolysis)

I: increased temp

V: VS instability (tachycardia/tachypnea and labile BP)

E: encephalopathy (agitation, confusion, delirium)

R: restlessness and incoordination

S: sweating

what is the first thing noticed when someone is experiencing encephalopathy

confusion

what are the nursing interventions for Serotonin Syndrome

- d/c medication

- maintain a safe environment

- monitor physical and mental status

- admin: serotonin receptor block; dantrolene or diazepam and cyproheptadine

- provide reassurance

what does diazepam or dantrolene do in serotonin syndrome

helps with muscle rigidity

what does cyproheptadine do in serotonin syndrome

serotonin receptor antagonist - blocks serotonin receptors

what is the MOA of TCAs

Block reuptake of NE and serotonin and blocks cholinergic receptors

what does TCA stand for

tricyclic antidepressant

TCAs are what kind of lipid solubility

high lipid solubility > narrow TI

what are some common SE of TCAs

- sedation

- mydriasis (dilation of pupil)

- weight gain

- sweating

- toxicity

- sexual dysfunction

- decreases seizure threshold

- orthostatic hypotenstion

- anticholinergic effects

TCAs toxicity is dangerous because they are

lethal in OD

what are the 3 common TCAs to know

amitriptyline, nortiptyline, imipramine

what are some key points for pt teaching of TCAs

- avoid alcohol

- lethal in OD

- take in evening

- use caution when driving

- take as prescribed

TCAs cause what in OD

cardiac arrythmias

what class of medication would is less likely to be prescribed TCAs if they have a hx of suicide attempts

TCAs

TCAs take how long to take effect

4-8 weeks

what is the MOA of Monoamine Oxidase Inhibitors (MAOIs)

blocks enzyme that breaks down NE, dopamine, and 5HT

what are the common SE of MAOIs

- muscle cramps

- weight gain

- sexual dysfunction

- anticholinergic effects

- serious food and drug interactions (tyramine)

what is tyramine

naturally occurring chemical found in some foods; has interactions with MAOIs

what are the key MAOIs to know

phenelzine and tranycypromine

what are some MAOI pt teaching points to educate on

- lethal in OD

- food and drug interactions with tyramine

- continue dietary restrictions for at least 2 weeks after drug d/c

- notify physician before taking any other med (Rx, OTC)

- use caution when driving

what foods should be avoided on an MAOI

- aged cheeses/meats

- foods with yeast

- soy

- beer/wine

- avocados/bananas

what happens if someone on an MAOI eats a food containing tyramine

tyramine + MAOI = too much norepinephrine → dangerous BP spike → hypertensive crisis

what are some hypertensive crisis S/S

- N/V

- chills

- sweating

- fever

- severe HTN

- restlessness

- nuchal rigidity

- dilated pupils

- occipital HA

- motor agitation

- severe nosebleeds

what is a distinct S/S of a HTN crisis

occipital HA

what are some classes of atypical depressants

SNRIs, SNDIs, SARIs

what are atypical antidepressants SNRIs also used for

neuropathic pain

why are atypical antidepressants SNRIs good for the elderly

fewer anticholinergic effects, used for neuropathic pain

what is the MOA of SNRIs

increase 5HT and NE

what is the MOA of SNDI

increase 5HT and NE

what are SNDIs usually used with

usually paired with SSRIs to help efficacy or counteract SE

what is the MAO for SARIs

blocks 5HT reuptake, blocks andrenergic receptors

what is helpful about SARIs

have sedating properties that are helpful for people with insomnia