Flashcards in Pharm Deck (212):
Effect of epinephrine at low and high dose
a-1, B1, B2
Low dose: Beta-2 vasodilation stronger (decrease DBP blood pressure)
High dose: alpha-1 constriction stronger (increase DBP blood pressure)
To prevent the low dose effects of epinephrine (lowered BP), what can you do?
Administer a beta blocker so everything goes to alpha constriction instead of Beta 1 (tachycardia) and beta 2 (vasodilation)
Succinylcholine side effects
1. hyperkalemia (arrhythmia)
2. malignant hyperthermia with halothane
Who is predisposed to succinylcholine toxicity of hyperK
pts with burns/myopathies, anything that would cause cell lysis
--Also pts with denervating dzs (quadriplegics)
GABAb muscle relaxant
Acts on ryanodine receptors, preventing release of calcium
--good for malignant hyperthermia
atracurium side effects
histamine release causing flushing, bronchoconstriction, hypotension.
If you're worried about hyperkalemia when giving succinylcholine what is a good alt med
vecuronium/rocuronium these are non-depolarizing AchR blockers
affinity of enzyme for substrate
Vmax is proportional to
Michaelis-mentin kinetics means
enzyme rxn follows a hyperbolic curve
Which types of drugs are metabolized by the liver?
--can be metabolized and excreted in bile/liver
Bioavailability of the drug is calculated through
Area under the curve, comparing oral with IV
Side effect of nitroglycerin
headaches and facial flushing from vasodilation of skin and meninges
Metformin is contraindicated in patients with
renal failure. Because lactic acid accumulates. In reality, metformin is contraindicated in anyone who might have lactic acidosis (alcoholic, septic, CHF)
which drugs require routine thyroid testing
lithium and amiodarone
selective muscarinic ACh antagonist that reduces the effect of the cholinesterase inhibitor
Intrinsic ability of a drug to have a desired outcome, expressed by MAXIMUM activity Emax
Dose of a drug required to produce a given effect. Determined by AFFINITY (1/Km) and the AMOUNT of drug able to reach target.
Lower the Ed50, high potency
--Dose of drug required to produce half of the full response
An alpha agonist. Vasopressor used for shock
Selective alpha-1 BLOCKER for HTN and benign prostatic hyperplasia. Thus, a vasodilator
Major B1, some B2 and A1
-Small increase in HR
Side effect of dobutamine
Increased cardiac conduction velocity=arrhythmias
--Also, increases myocardial oxygen consumption (higher heart rate and contractility)
--Nitrates increase heart rate, but also decreases preload, reducing myo o2 consumption
Competitive inhibitor effect on Km
noncompetitive inhibitor effect on Km
which type of inhibitor will decrease potency?
which type of inhibitor will affect efficacy?
Calculate volume of distribution
amount of drug/plasma drug concentration
which type of drugs stay in the blood
large, charge molecules
which drugs go to ECF
small hydrophilic molecules
which drugs go to all tissues
small lipophilic molecules
Cp x Vd/F
Cp x CL/F
Which drugs have zero order elimination?
Pt overdoses with weak acid what do you do?
Give bicarb--charges molecule for elimination
Pt overdoses with weak base. What do you do?
Give ammonium chloride acid NH4Cl--Charges molecule for elimination
example of weak acid drugs
example of weak base drug
Phase I metabolism
reduction, oxidation, hydrolysis with cytochrome P-450. Makes drug more polar but still active
Phase II metabolism
glucuronidation, acetylation, sulfation
--makes polar and inactive metabolites
slow metabolizers of drug. increase risk of side effects
First order elimination
constant fraction of drug is excreted
Partial agonist effect
effect on potency is variable
therapeutic window is the range btw
minimum effective to minimum toxic dose
Sympathetic sweat glands innervated by
Sympathetic renal vasculature innervated by
Adrenal medulla innervated by
Nicotinic Ach receptor. Does NOT go through the sympathetic chain!
Nicotinic ACh receptors are what type of receptors?
Ligand-gated Na/K channels
Nn vs Nm receptors?
Nn are nicotinic receptors found in autonomic ganglia Nm are found in neuromuscular junctions
What type of receptors are muscarinics?
G protein receptors with 2nd messengers
CNS and enteric nervous system
decrease heart rate/contractility
increase exocrine secretions, peristalsis
ciliary muscle contraction
pupillary sphincter contraction
dilation pupillary dilator
intestinal/bladder sphincter contraction
-CNS mediated decrease in blood pressure
-Decrease aqueous humor fluid production
-inhibition of lipolysis
-inhibition of adrenergic and cholinergic release
-increased platelet aggregation
causes renin release
increased heart rate/contractility
ciliary muscle relaxation
aqueous humor production
decreased uterine tone
relaxes renal vascular smooth muscle
contraction of bronchioles
gastric acid secretion
vascular smooth muscle contraction
Increased permeability in collecting tubules
Gprotein class of D1, D2
Gprotein class of H1, H2
Gprotein class of V1, V2
Which receptors work through Gq?
which receptors work through Gi?
Describe the Gq pathway
Phospholipase C activated
-converts lipids to PIP2
-PIP2-->DAG and IP3
-IP3 increases [Ca]in
-DAG activates protein kinase C
Describe the Gs pathway
Activation of adenylyl cyclase
-Activation of protein kinase A
-myosin light chain kinase increases
what controls release of NE?
NE negative feedback to alpha-2
AII receptor (+)
M2 receptor (-)
acetylcholine is made from
AcetylCoA + Choline ChAT
NE is made from
blocks choline entry into cholinergic neuron
inhibits synthesis of Ach
prevents release of ACh
Cocaine, TCA, amphetamines
Inhibit NE reuptake
also iincrease release of NE inaddition to reducing reuptake
inhibits release of NE
-Activates bowel and bladder for postoperative ileus and urinary retention
open and closed angle glaucoma. Contracts ciliary muscle and pupillary sphincter
Causes sweat, tears, and saliva
-reversal of NMJ blockate
Does neostigmine penetrate CNS?
long acting AChE inhibitor for MG
Does pyridostigmine cross BBB?
used to diagnose myasthenia gravis. short acting AChEI
atropine poisoning. crosses BBB to reverse ACh block
AChE inhibitor. Increases Ach in the brain for alzheimer's patients
AChE inhibitor poisoning. Causes too much Acetylcholine!
Diarrhea, urination, miosis, bronchospasm, bradycardia, excitation of muscle/CNS, Lacrimation, Sweating, Salivation
Antidote for organophosphate poisoning
atropine and pralidoxime
What is atropine used for?
pupil dilation, relaxation of the ciliary muscle
Also to treat bradycardia
HOT as ahare
Dry as a bone
MAD as a hatter
RED as a beet
BLIND as a bat
What do you NOT want to give to someone with acute close angle glaucoma?
Anything that will cause mydriasis (pupil to dilate)
-alpha 1 activator
-atropine (blocks M3 which activates pupillary sphincter)
atropine causes what in men with BPH?
atropine causes what in infants?
What is the problem with giving a D2 blockade?
This is how antipsychotics work!
--will cause depletion of dopamine
--drug induced parkinsonism (extrapyramidal effects of typical antipsychotics)
How do you treat drug induced parkinsonism?
Give anticholinergics like benztropine or amantadine. These inhibit dopamine reuptake
What can you use to dilate the eye?
Ipratropium, tiotropium mechanism
reduce urgency in mild cystitis
parenteral: reduce airway secretions before surgery
Oral: drooling or a peptic ulcer
glucoma (open angle), asthma, hypotension
alpha 1 on the eye
B2 on the eye
ciliary muscle relaxation, aqueous humor production
activates B1 and B2
torsade de point and bradyarrhythmia
a1, a2, b1 (less so)
high dose dopamine activates
alpha 1 and alpha 2
low dose dopa activates
D1. good for maintaining renal perfusion when treating shock patients
medium dose dopa activates
heart failure, cardiac stress stesting
B2, some B1
premature uterine contractions
Applications of Ritodrine
Reduces premature uterine contractions
amphetamine and ephdrine mechanism
releases stored catecholamines.
What should you never give to someone who has overdosed on cocaine?
beta blockers. Leads to unopposed alpha1 activation
effect of Norepi on BP and HR
Increase in BP, reflex decrease in HR (mostly alpha-1)
effect of isoproterenol on BP and HR
Increase in HR (B1)
Drop in BP (Mostly B2)
When to use clonidine/a-methyldopa?
hypertension in peeps with renal disease (preserves flow to kidneys)
How does clonidine work?
Centrally at the alpha 2 agonists to decrease sympathetic outflow
Indication for phenoxybenzamine?
--before removing tumor--it's an IRREVERSIBLE alpha blocker!
Indication for phentolamine?
pts in HTN crisis from eating tyramine while taking MAO-I
--it's reversible :)
What does tyramine do?
It is a catecholamine releasing agent
terazosin, doxazosin, tamsulosin
alpha-1 selective blockers
Indication for tamsulosin
Hypertension, urinary retention in BPH
side effect of alpha blockers
first dose orthostatic hypotension
alpha 2 selective blocker
indications of mirtazapine
side effect of mirtazapine
increased appetite and cholesterol
Effect of epi +alpha blockade
decreased blood pressure (b2 effect takes over)
effect of phenylephrine + alpha blockade
Normal blood pressure
Decreases secretion of aqueous humor in glaucoma
Who do you NOT want to give a beta blocker to?
asthmatics (if non-selective)
diabetics (beta 2 increases insulin secretion. blocking it will decrease insulin secretion)
side effect of beta blockers
impotence, bradycardia, sedation
which are the selective beta blockers?
(A BEAM of b1blockers)
Non-selective beta blockers
which beta blockers also work as partial agonists?
pindolol and acebutolol
which drugs are nonselective alpha and beta blockers?
carvedilol and acebutolol
Treatment for salicylate overdose
Treatment for lead poisoning
Treatment for mercury overdose
Treatment for arsenic/gold
dimercaprol, succimer, penicillamine
Treatment for copper overdose
Treatment for methemoglobin
vitamin C or methylene blue
Treatment for methanol/ethylene glycol
Treatment for TCA overdose
NaHCO3 (plasma alkalinization)
Treatment of tPA/streptokinase, urokinase overdose?
Treatment of theophylline overdose
st. john's wort
chronic alcohol use
Momma barb steals Phenphen and Refuses Greasy Carbs Chronically
MAGIC RACKS in GQ
acute alcohol abuse
consequences of sulfa allergies
Stevens Johnson, Hemolytic anemia
GO THROUGH DRUG RXNS on PG 240!!
inhibits squalene 2 3 epoxidase, decreasing ergosterold synthesis
binds to ergosterol in fungal cell MEMBRANE forming pores
binds microtubules and inhibits mitosis
binds 1, 3 beta D glucan and blocks glucan synthesis
inhibits DNA and RNA synthesis in fungal cells. Used in combo with ampho B for cryptococcus
Blocks endothelin receptors. Used to treat primary pulmonary arterial hypertension
monoclonal antibody that binds TNF-alpha used for RA and psoriasis
Drugs that induce CYP 450
Drugs that inhibit CYP 450
which drugs prolong the QT interval?
Class III antiarrythmics (Potassium Channel blockers)
short acting benzos
how do u prevent flushing associated with Nitroglycerin?
administer aspirin beforehand. Reduces prostaglandins. . nicotinic acid also helps
caspaicin works by
decreasing the level of substance P in the PNS
Replace uracil with 5-FU in fungal mRNA
A woman with bradycardia after MI...treatment with?
atropine to block vagus from contacting the SA/AV nodes
Digoxin and adenosine antiarrythmic effect
Slow conduction through AV node
Class I A antiarrythmic
Blocks sodium channels. Decreases depolarization and phase III repolarization
Class IB antiarrythmic
Blocks sodium channels in very rapidly depolarizing cells.
Class IC antiarrythmic
blocks sodium channels and slows phase 0
Dopamine derivative. D1 agonist ONLY, no effect on alpha/beta.
--reduces vascular resistance by dilating renal, mesenteric, coronary beds
The only agent that improves renal perfusion while lowering blood pressure
arterial vasodilators and decrease HR/contractility
arterial vasodilator. use in pregnancies.
arterial AND venous dilator, most effective for HTN crisis
Side effects of nicardipine
A dihydropyridine CCB: tachycardia, flushing, headache
Traditional high potency anti-psychotics
traditional low potency antipsychotics
Benefits of 2nd generation antipsychotics?
Improve BOTH positive and negative symptoms. Older 2nd generation antipsychotics only stopped the positive symptoms
Side effect of high potency antipsychotics
side effect of low potency antipsychotics
anticholinergic and histamine side effects
dystrophin gene is on
X chromosome p21 with a frameshift mutation, resulting in deltion. Becker's is an insertion of three base pairs, causing a milder form
Side effect of methotrexate
Side effect of hydroxychloroquin
permanent retinal damage
main mechanism of nitroglycerin
Platelets predominantly express COX1 or COX 2?
--expressed in normally functioning tissue
COX2 only expressed in inflammatory tissue