MRAD 2410: Module 3 (P1: Pharmaceuticals)

main role of adrenergic drugs

vasoconstriction

in what scenarios are adrenergic drugs used

life threatening conditions: cardiac arrest, shock, asthma attack, allergic reactions

mechanism of action of adrenergic drugs

bind to adrenergic receptors in the body (alpha 1/2, beta 1/2/3) and mimic the action of epinephrine or norepinephrine, or stimulate their release

effects of adrenergic drugs (5)

increase BP, constrict blood vessels, open the airways to the lungs, increase HR, stop bleeding

example of an adrenergic drug

epinephrine (adrenalin)

role of local anesthetics

eliminate sensation in specific areas

mechanism of action of local anesthetics

they block sodium from entering a nerve ending at the site of pain = pain receptors don’t activate

how are local anesthetics delivered

topically or injected

what drug are local anesthetics often paired with + why

epinephrine (adrenergic drug): this constricts blood vessels, so the anesthetic only blocks the nerves in the area it’s injected

example of local anesthetic

lidocaine

what does general anesthesia do

pt goes unconscious, requires mechanical ventilation

examples of general anesthesia (3)

pentothol, fluothane, nitrous oxide

what do antagonists do

reverse the effects of an administered medication

give two examples of antagonists

ramazicon, narcan

what does romazicon (an antagonist) do

counterattacks the effects of sedatives and analgesics (wakes the pt up)

mechanism of action of romazicon (an antagonist)

competes with benzodiazepines for GABA receptors, which are responsible for inducing sleep and controlling anxiety = pt wakes up

when is romazicon (an antagonist) used in medical imaging

when sedation wasn’t needed for as long as anticipated; works in 1-2 minutes

how is romazicon (an antagonist) given

intravenously

role of narcan

counteracts the effects of narcotics

mechanism of action for narcan

competes with micro-opioid receptors in the CNS

effects of narcan

prevents respiratory depression, sedation, and hypotension

side effects of narcan

nausea, vomiting, tachycardia, nervousness

how is narcan given

subcutaneously or intramuscularly

when will narcan be used in medical imaging

when the pt was given too much analgesia or if the exam needs to be ended prematurely

how long does narcan last

45 min

role of anti-anxiety meds

manage anxiety prior to procedures, prevent/control seizures, stop an ongoing series of seizures

mechanism of action for anti-anxiety meds

they enhance the effects of GABA in the brain = brain activity is inhibited = brain relaxes

side effects of anti anxiety meds

drowsiness, irritability, nausea, skin rash, lack of physical coordination

common anti anxiety meds

barbituates, benzodiazepines, opiates

role of thrombolytics

break up existing clots

thrombolytics break up existing clots. what types of ppl might have clots

those who recently hard a myocardial infarction, acute secondary stroke, or lower leg ischemia

what issue might occur with thrombolytics

pt are prone to bleeding internally and externally, so we need to be very careful when initiating and managing their lines

common thrombolytic

activase

role of anticoagulants

prevent clot formation

what pts will we use anticoagulants on

those prone to blood clot formation or who have a history of blood clot formation

two methods of anticoagulant administration

orally, intravenously

mechanism of action of oral anticoagulants

prevent vitamin K absorption in the intestines = prevents formation of clotting factors

example of oral anticoagulant

warfarin

mechanism of action of intravenous anticoagulants

increases the thrombin time in the blood = inhibits thrombin from forming blood clots

example of intravenous anticoagulant

heparin

role of warfarin

used to prevent strokes, heart attacks, and blood clots

what if a pt is due for an exam but they take warfarin

they may be asked to discontinue use from 1-6 days prior

plavix is another anticoagulant. how does it work

protects against future incidences by preventing the formation of platelets in the blood

how long after plavix administration do platelets stop forming, and when do they form again

stop forming after 2 hours, continue 8-9 days later

aspirin is another anticoagulant. what does it do

permanently inactivates platelets, lasting 7-10 days

role of anticholinergics

block the effects of acetylcholine

effects of anticholinergics

reduce airway secretions/resistance, help with urinary incontinence or overactive bladder, help with COPD, help with poisoning, help with parkinson’s spams, help with intestinal spasms

common anticholinergic

buscopan

role of antidepressants

treat clinical depression

mechanism of action of antidepressants

increase serotonin and NE levels

what is the most commonly prescribed type of antidepressant

SSRIs

describe type 1 diabetes

pt can’t produce insulin so they’re insulin dependent

describe type 2 diabetes

pt can produce insulin but the body doesn’t effectively use it, so they require durgs

what is a common antidiabetic/hypoglycemic medication

metformin

mechanism of action of metformin

processed by the kidneys and raises creatinine levels in the blood

metformin is processed (excreted) by the kidneys. but what if the kidneys aren’t working well? what dangers does this cause

metformin can increase the risk of lactic acidosis, especially when iodinated contrast in given in imaging exams

since metformin can increase the risk of lactic acidosis, especially when iodinated contrast in given in imaging exams, what do we do

pt stops taking metformin hours-days before a contrast scan and isn’t restarted until days after

why are diabetics booked for exams/procedures first thing in the morning

certain exams are NPO, and we don’t want the pt to get low blood sugar or they could have a seizure/coma

cause of ketoacidosis

increased sugar consumption

effects of ketoacidosis

increased thirst and urinary output, decreased appetite, nausea, vomiting, weakness, confusion, coma

ketoacidosis treatment

insulin

cause of insulin reaction

excessive exercise, insufficient food post-insulin intake

symptoms of insulin reaction

headache, hunger, cold/clammy skin, tremors, tachycardia, impaired vision, personality change, LOC

treatment for insulin reaction

administer food/liquid with high sugar content, administer glucagon

what is antihistamine used for

allergy relief

what is antihistamine used for in medical imaging

used to prevent allergic reactions prior to iodinated contrast media injects

define prophylaxis

to prevent

describe first generation antihistamine agents

available over the counter, cause sedation and are used as sleep aids, highly effective in symptomatic treatment

example first generation antihistamine agent

benadryl

describe second generation antihistamine agents

favoured by clinicians due to safety and efficacy, effective for nasal congestion relief

example of second generation antihistamine agent

allegra

the only treatment for severe anaphylaxis is ____

epinephrine

what are beta blockers used for

acute attacks of tachycardia or fibrillation

mechanism of action for beta blockers

block the effects of circulating NE on the heart = reduces the effects of physical exertion on HR and contraction

side effects of beta blockers

nausea, vomiting, diarrhea, skin rash, hallucinations

example of beta blocker

propranolol

what do bronchodilators do

dilate the bronchioles by making the muscles relax = facilitates breathing

list the 2 types of bronchodilators

beta-2 agonist, anticholinergic

what are beta-2 agonists used for (bronchodilators)

used for asthma and COPD

mechanism of action of beta-2 agonists (bronchodilators)

stimulate beta-2 receptors in the muscles that line the airways = causes them to relax = airways dilate

what two forms of beta-2 agonists (bronchodilators) are there

long-acting, short-acting

who shouldn’t be given beta-2 agonists (bronchodilators)

people with hyperthyroidism, CVD, arrhythmia, hypertension, diabetes

what are anticholinergics (bronchodilators) used for

COPD

mechanism of action of anticholinergics (bronchodilators)

block cholinergic nerves = airway muscles relax = airways dilate

what are cathartic drugs

laxatives/purgatives

what are cathartic drugs used for

pre-procedural prep for GI exams

what are diuretics commonly referred to as

water pills

role/mechanism of action of diuretics

get rid of sodium in the body and assist the kidneys in releasing more sodium into the urine

what do diuretics do to BP

decrease it

most common diuretic

lasix

who is lasix prescribed to

pts who retain fluid, have CHF, liver disease, or hypertension

side effect of diuretics

fluid and electrolyte imbalance

do diuretics hydrate or dehydrate

dehydrate

what does NSAID stand for

non-steroidal anti-inflammatory drug

what are glucocorticoid/NSAIDs used for

treat pain associated with inflammation

examples of glucocorticoids/NSAIDs

aspirin, ibuprofen, naproxen

mechanism of action of glucocorticoids/NSAIDs

block enzymes and reduce prostaglandins that promote inflammation/pain/fever

side effect of glucocorticoids/NSAIDs

stomach ulcers + bleeding

why can glucocorticoids/NSAIDs cause stomach ulcers

prostaglandins protect stomach lining, and glucocorticoids/NSAIDs block prostaglandins

what are narcotics referred to as

opiates