pharm 2 Flashcards
Oral drugs – undergo
1st pass metabolism in liver.
What is used to determine whether a drug will cross glomerulus: attached to a protein or not;
acid or base; positive or negatively charged
attached to a protein or not
Which drug absorbs better in stomach acid?
Weak acid
In order for a drug to do its effect in what state should it be? Weak acid, Weak base Liposoluble Hydrophobic Hydrophilic
Liposoluble
- NON ionized drugs are soluble in lipid.
When a drug does not exert its maximum effect is because it’s bound to?
Albumin
Which of the following best explains why drugs that are highly ionized tend to be more rapidly excreted than those that are less ionized? The highly ionized are A. less lipid soluble. B. less water soluble. C. more rapidly metabolized. D. more extensively bound to tissue.
A. less lipid soluble.
Therapeutic Index LD/ED is a measure of:
safety of drug
QUESTION: LD50 means at this dose,
50% of the test animals died
QUESTION: What is bioavailability of a drug?
amount of drug that is available in blood
What does bioavailability measured?
How much drug is absorbed in the circulation
Blood to urine ratio
How much drug is absorbed in the circulation
What pharmacokinetic factor influences the need for multiple doses in a day (dose rate)? half-life; bioavailability, or
clearance
half-life
Two different drugs with same dosages, bind to the same receptor, and cause same intrinsic affect. However, they have different
affinities for the receptor. In which aspect these 2 drugs are similar?
a. ED50
b. LD50
c. Potency
d. Efficacy
- Efficacy bc they can both produce the same maximal response if enough is given
Fixed dose drug A w/ low dose of Drug B increase drug B effect when same dose of drug a is give w/ increased does of drug B:
competitive antagonist, synergism, partial agonist
- partial agonists bind & activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist.
Three carpules (2 ml carpules, 40 mg/ml) of local anesthetic X are required to obtain adequate local anesthesia. To obtain the same
degree of anesthesia with local anesthetic Y, five carpules (2 ml carpules, 40 mg/ml) are required. If no other information about the two drugs is
available, then it is accurate to say that drug X:
is less potent than drug Y.
is more efficacious than Y.
is less efficacious than drug Y.
X&Y are = in potency & efficacy.
X is more potent
no info on efficacy really
if ceiling effect was the same but with different doses,
efficacy would be the same
The maximal or "ceiling" effect of a drug is also correctly referred to as the drug's A. agonism. B. potency. C. efficacy. D. specificity.
efficacy
vagal reflex
reflex to suddenly increased BP –> slows down HR
can give atropine to block
Epinephrine reversal –
when also taking α blocker (ex. prazosin, chlorpromazine) cause decrease in BP b/c β-mediated vasodilation
predominates
o Beta2 trumps A1 so vasodilation happens & BP decreases
Alpha-1 agonist:
increase smooth muscle tone, vasoconstrictor –> ↑ BP
Alpha-2 agonist:
given orally b/c they cause hypotension by reducing sympathetic CNS outflow
What does Alpha-1 do?
Vasoconstriction of peripheral vessels (smooth muscle)
When you stimulate alpha 1 receptors what happens?
a. Vasoconstriction
b. Hypertension
Vasoconstriction
What does alpha-1 receptors do to the heart?
Vasoconstriction, increase blood pressure, increase peripheral resistance, mydriasis
(pupil dilution) and urinary retention
Adrenalin – stimulates which receptors
alpha 1, 2 and beta 1, 2 receptors
Heart has which receptors.
beta-1
Slow infusion of epinephrine will cause which of the following and know which receptor is responsible -
Alpha 1 (Vasoconstriction during anaphylaxis), Beta 1 (Increases cardiac output), Beta 2 (bronchodilation)
Patients BP spike after EPI, what receptor?
B1
Hemostatic agents in retraction cord target what receptor? • a1 • b1 • b2 • gaba • muscarinic receptor
a1 (vasoconstriction)
Retraction cord with epinephrine can cause:
increase HR, BP
- do not use in hyperthyroid or cardiac disease.
After using a gingival retraction cord, tissue reacts by recession. Where do you see this the most? Lingual, buccal, interproximal.
buccal
Smooth muscle relaxation is caused by which of the following drugs?
a. prazosin
b. atropine
c. theophylline
d. amphetamine
a. prazosin (alpha 1 blocker…blocks vascular smooth muscle constriction)
b. atropine (anticholinergic)
c. theophylline (treat asthma, COPD…it relaxes bronchial smooth muscle…so I guess it does do smooth muscle…)
d. amphetamine (psychostimulant…increase wakefulness)
- answer should be an alpha-1 antagonist/blocker
Which of the following combinations of agents would be necessary to block the cardiovascular effects produced by the injection of a sympathomimetic drug? Atropine and prazosin Atropine and propranolol Prazosin and propranolol Phenoxybenzamine and curare Amphetamine and propranolol
Prazosin and propranolol
- sympathomimetic drug injection (ex. NE) stimulates α/β receptors so α-blocker prazosin + β blocker propranolol is needed.
- Atropine is an muscarinic/cholinergic receptor blocker that would stimulate heart (opposite effect)
Each of the following drugs produces vasoconstriction of vessels if injected into the gingiva EXCEPT one. Which one is this EXCEPTION? Epinephrine (EpiPen®) Terazosin (Hytrin®) Levonordefrin (Neo-Nedfrin®) Phenylephrine (Neo-Synephrine®) Norepinephrine (Levophed®)
- Terazosin, selective alpha-1 antagonist, is used to tx HTN & enlarged prostate (BPH)
Epinephrine + propanolol:
increases BP, decreases HR
Propranolol is a nonselective beta blocker so epi only acts at only alpha receptors, which in the periphery are mainly alpha-1 receptors
- This causes vasoconstriction &Increased ⬆ BP –> increased firing, which triggers aortic and carotid sinuses –> increased vagal activity
on the heart –> decreased
⬇ HR.
If using with epi, Change propranolol for?
Metoprolol … little change on HR, but no marked increase in BP.
- METOPROLOL = selective B blocker (proprano is nonselective) and is ok to use with EPI!
Propranolol + epinephrine = bad reaction due to: drug interaction, anxiety, allergy
drug interaction,
Patient taking propranolol with epinephrine. What receptor caused hypertensive crisis?
- alpha 1
- alpha 2
- beta 1
- beta 2
alpha-1
- If a patient on a nonselective beta-blocker receives a systemic dose of epinephrine, however, the beta-blocker prevents the
vasodilation, leaving unopposed alpha vasoconstriction. (alpha-1)
What is the effect seen when propranolol and epinephrine are injected simultaneously -
in cases of mild reactions it causes
hypotension; in severe reaction it is malignant hypertension
All these drugs alter ionic movement except - Propranolol, CCB, HCTZ, and Digoxin
Propranolol
QUESTION: A patient receiving propranolol has an acute asthmatic attack while undergoing dental treatment. The most useful agent for management to the condition is? a. Morphine b. Epinephrine c. Phentolamine d. Aminophylline e. Norepinephrine
- Aminophylline: Bronchodilator, class theophylline
The drug-of-choice for the treatment of adrenergically-induced arrhythmias is: quinidine. lidocaine. phenytoin. propranolol
propranolol
Direct alpha sympathomimetic: clonidine, guanethidine , methyldopa
clonidine
guanethidine is indirect - acts on neurons to inhibit NE release
methldopa is fake neurotransmitter
Epinephrine Reversal with?
Alpha adrenoceptor blockers (ex. phenoxybenzamine)
- inhibit the vasoconstrictor effect but not the vasodilator effect of epinephrine = low BP instead of high BP
Epinephrine reversal: after giving a patient epinephrine, following hypertension, which of these drugs would cause a drop in BP?
Phenoxybenzamine
What receptor or signaling pathway is linked most directly to α2-adrenoceptor stimulation? I
nhibition of adenylyl cyclase through
GI, resulting from stimulation of α2-adrenergic receptor, leads to intracellular ⬇ cAMP
amphetamines MOA
indirect-acting sympathomimetics
ADHD meds
Methylphenidate = Ritalin
o Methylphenidate: blocks dopamine uptake in central adrenergic neurons by blocking dopamine transport or carrier proteins.
- Amphetamine = Adderall
o Amphetamines & cocaine: increase catecholamine NE SERETONIN DOPAMINE release as a primary mechanism.
§ Amphetamines stimulate CNS alpha receptors
o Adderall: psychostimulant medication composed of amphetamine and dextroamphetamine, which increases the amount of
dopamine and norepinephrine in the brain
ADHD with gender
M>F
Amphetamines MOA –
lead to NE release in brain
- stimulate the release of norepinephrine from central adrenergic receptors & at higher dosage, release of dopamine
Methylphenidate brand name, Amphetamine brand name
Methylphenidate = Ritalin, Amphetamine = Adderall.
Kid is taking Adderall (amphetamine) & is very anxious what do you do?
Tell him to stop taking amphetamine on the day
appointment
- Amphetamine can induce anxiety, and are contraindicated for patients that are very nervous
Side effect of Amphetamines
– Insomnia (difficulty of falling asleep)
Amphetamines, what are symptoms?
Increased heart rate & excitability
Cholinergic crisis:
bradycardia, lacrimation, salivation, voluntary muscle weakness, diarrhea, bronchoconstriction – tx w/ atropine
cholinergic agonists: examples and effect on slivation
increased salivation
pilocarpine (direct), neostigmine
anticholinergic agents
atropine/scopolamine
antticholinergic overdose
confusion, hallucinations, burning mouth, hyperthermia – tx w/ physostigmine
direct cholinergic agonist
pilocarpine, methacholine (xerostomia)
indirect acting cholinergic agonists MOA
prevent enzyme breakdown
reversible anti-cholinesterase: physostigmine (CNS and PNS) and neostigmine (PNS only)
irreversible = insecticides and organophosphates
tx overdose with pralidoxime
Competitive muscarinic receptor blockers =
Atropine, scopolamine, propantheline
What is used for motion sickness?
scopolamine
Neostigmine and pilocarpine increase?
Salivation
- Pilocarpine (muscarinic agonist) & neostigmine are parasympathomimetic that acts as a reversible acetylcholinesterase inhibitor. They
increase salivation, urination, bronchoconstriction, bradycardia, miosis (pupil constrict), vasodilation
Glycopyrrolate effect?
reduce salivary (muscarinic anticholinergic)
Atropine: _____ salivation
decrease
What meds decrease saliva?
atropine, scopolamine
- Pilocarpine, methacholine, neostigmine, etc. cause salivation.
QUESTION: If patient has xerostomia, what medication won’t you give?
Atropine - anticholinergic
What drug does not cause miosis of the eyes?
Atropine
Pt have bradycardia, what should we give him?
Atropine b/c atropine will increase heartrate causing tachycardia.
Drug to decrease saliva because you want to take an impression- Atropine, Pilocarpine, Neostigmine
ATROPINE
Atropine poisoning tx:
physostigmine
Patient salivates a lot, what is tx before surgery?
Atropine **antimuscarinic
Xerostomic pt, give
pilocarpaine or cevimeline.
- Cimeviline just like pilocarpine to increase salivation in xerostomia
What drug do you give to a pt with xerostomia?
Pilocarpine
Pilocarpine used for?
parasympathomimetic alkaloid, for tx of glaucoma and xerostomia.
What is the side effect of pilocarpine (Tx of dry mouth) in toxic dose?
Bradycardia and hypotension
Apnea
Cardiac shock
Bradycardia and hypotension
- nontoxic side effects»> excess sweating and salivation, bronchospasm
Propantheline bromide (pro-Banthine):
anti-cholinergic (anti-muscarinic), relieve cramps or spasms of the stomach, intestines, and
bladder.
Which of the following groups of drugs is contraindicated for patients who have glaucoma? Adrenergic, Cholinergic, Anticholinergic
Adrenergic blocking
Anticholinergic
Which of the following drug groups increases intraocular pressure and is, therefore, contraindicated in patients with glaucoma? A. Catecholamines B. Belladonna alkaloids C. Anticholinesterases D. Organophosphates
B. Belladonna alkaloids – anti-cholinergic
organophosphates are irreversible cholinesterase inhibitors; indirect agonists
tubocurarine
inhibits ACH receptor –> weakness of skeletal muscles
Decrease of pseudocholinesterase would lead to increase in? Succinylcholine or tubocurare
Succinylcholine
Administration of succinylcholine to patient deficient in serum cholinesterase would cause…
a. convulsions
b. Hypertension
c. prolonged apnea
d. Acute asthma attack
c. prolonged apnea
miosis can be caused by which drigs
opioids and cholinergics
mydriasis can be caused by which drugs
anticholinergics and increased serotonin
A patient who has Parkinson’s disease is being treated with levodopa. Which of the following characterizes this drug’s central
mechanism of action?
a. it replenishes a deficiency of dopamine
b. it increases concentrations of norepinephrine
c. it stimulates specific L-dopa receptors
d. it acts through a direct serotonergic action
a. it replenishes a deficiency of dopamine
Cause of Parkinson?
Dopamine deficiency, give them methyldopa (levodopa) to increase dopamine in the CNS
Why do you need to take carbidopa with levodopa:
prevents breakdown of levodopa before it crosses the blood brain barrier
Carbidopa addition prevents levodopa from being converted into
dopamine in the bloodstream, peripheral enzymatic degradation so more reaches the brain.
How does carbidopa tx Parkinson’s disease?
potentiates effects of dopamine
anti-psychotics effect
sedate, blunt emotional expression, attenuate aggressive & impulsive behavior.
anti-psychotics adverse effects
Produce anticholinergic adverse effects,
dystonias and extrapyramidal symptoms. Tardive dyskinesia most common after several years.
tardive dyskinesia whose side effect
anti-psychotics
phenothiazine
Phenothiazines (PTZ) MOA :
Block DA receptors, act on the extrapyramidal pathway
Where in the brain does anti-psychotics works?
blocking the absorption of dopamine
extrapyramidal pathways
What catecholamine does Phenothiazine (anti-psychotic) affect? Dopamine, serotonin, acetylcholine
Dopamine
Phenothiazine side effect:
Tardive Dyskinesia
proverbial anti-psychotic
phenothiazine
What acts on extrapyramidal?
Phenothiazines (chlorpromazine)
Onset of action of antipsychotic is:
5-6 days
Lithium is used for treatment of?
Manic phase of bipolar disorder
Patient is in her 70’s, she lives alone, what could she be suffering from?
Depression
Most common psychological problem in elderly?
Depression
Old people have dementia as the most prominent psychiatric issue:
depression
What is associated with depression? Age, economic status, professional status, etc
Age
Most common mental illness among elderly?
Depression
Main sign of dementia: a. confusion b. short term memory loss c. long term memory loss -
b. short term memory loss
short term memory loss = first main sign. Long term loss occurs later.
Where in the brain does anti-depressants works?
decrease amine-mediated neurotransmission in the brain
Tricyclic anti-depressant (TCA) mechanism of action:
inhibit reuptake of NE and 5-HT (serotonin)
TCA 2nd generation-
-triptylines and -pramines
How do tricyclics work?- by
not allowing reuptake of neurotransmitter (NE, 5-HT, serotonin)
What catecholamine do tricyclic antidepressants affect? Dopamine, serotonin, acetylcholine
serotonin
Patient is taking TCA anti-depressants what do you take into consideration? Limit duration of procedures, keep in mind the
epinephrine limit
keep in mind the
epinephrine limit
Side effect of having TCA and epi: HTN, hypotension, hyperglycemia, hypoglycemia
HTN
Most common antidepressant does what?
- Inhibits reuptake of NE, 5-HT, & DA (TCA)
- Inhibit reuptake of 5-HT (SSRI)
- Inhibit reuptake of N & 5-HT (SNRI)
- Inhibit MAO; prevent breakdown of NE & 5-HT (MAOI)
- Block D2 receptor (phenothiazine)
If someone has a history of depression & wants to quit smoking, what do you give?
Zyban (Bupropion), it’s an anti-depressant &
smoking cessation aid
- not Chantix (smoke cessation only)
Amitriptyline –
most common tricyclic antidepressant, inhibits reuptake of NE and serotonin
Zoloft works on what receptor?
Presynaptic monoamine transporters (inhibit reuptake of 5-ht)
- Sertraline hydrochloride (Zoloft) = selective serotonin reuptake inhibitor (SSRI)
Prozac (fluoxetine) -
acts on serotonin (SSRI)
What do you use St. John’s Wart?
Depression
- St. John’s Wart = noncompetitive reuptake inhibitor of serotonin yeah because is for depression
What does St. John’s Wart do (side effect)?
Decrease the body immunity
St johns wart- used for?
Depression, don’t use with benz and HIV medication
- In HIV pt, it interacts w/ anti-HIV drugs & reduces their function so the immunity decreases
Know drugs used for conscious sedation à
SSRIs/BDZ Diazepam and Prozac (fluoexitine)
Buspirone -
psychotropic w. anxiolytic; low CNS depression, low psychomotor skill impairment
- Buspar—different from benzodiazepines because it does NOT cause CNS depression, muscle relaxant, or anti-convulsant!!!!!** UNIQUE!!!
Anxiolytic and antidepressant
side effect of corticosteroids
gastric ulcers, immunosuppression, acute adrenal insufficiency, osteoporosis, hyperglycemia, redistribution of body fat.
Strongest glucocorticoid/long-acting Corticosteroid?
Dexamethasone
Negative effect of chronic use glucocorticoids? In
fection, reduce inflammation, hyperglycemia.
GI effects with corticosteroids: .
Ulcers
Long term side effect of corticosteroids-
osteoporosis and hyperglycemia
What is the side effect of prolonged corticosteroid therapy?
Osteoporosis
Too much cortisone causes what to bone?
Osteoporosis
Osteopetrosis
Osteosclerosis
Osteoporosis
Where do you see moon faces?
steroid treatment
Containdation for corticosteroid use:
diabetes (also: HIV, TUBERCULOSIS, CADIDIASIS, PEPTIC ULCER)
Aspirin contraindicated with:
corticosteroid use
Critical dose of steroids for adrenal insufficiencies -
20 mg of cortisone or its equivalent daily, for 2 weeks within 2 years of dental
treatment
QUESTION: Least amount of cortisone to affect the adrenergic system?
2 mg for 2 weeks for 2 years
Pt taking corticosteroid with rheumatoid arthritis, pt needs TE, why would you consult with physician?
full blood panel, assess for
adrenal insufficiency
- want to make sure pt can produce enough corticosteroid with addition to what they are taking so you won’t have over inflammatory
response from TE
Pt on 3 months tx of steroids, what is your tx?
no tx and consult GP for dose
If a pt. has been using 10 mg of corticosteroid for 10 years, what would you do for pt. before any tx?
Have pt continue and increase
the dose
Cortisone exerts its action by binding to intracellular receptor, receptors on membrane, proteins in plasma
intracellular receptor
- Enter cell and bind to cytosolic receptor migrate to nucleus gene expression or with plasma membrane on target cells
QUESTION: If pt doesn’t get steroid tx in time for their temporal vasculitis, what will have happened?
• hearing loss
• vision loss
• retro-ocular headache
• vision loss
Asthma – long-term asthma give corticosteroid to
decrease inflammation
- Inhaled corticosteroids are the most effective medications to reduce airway inflammation and mucus production.
absolute contraindication for nitrous oxide
severe respiratory compromised, COPD, respiratory infection, pneumothorax/collapsed lung
relative contraindications for nitrous
cardiovascular conditions, pregnancy (teratogenic effect), nasal congestion, children with high anxiety,
Nitrous oxide is in which container
blue cylinder (oxygen in green)
Nitrous oxide MOA
oxidizes the cobalt in vitamin B12, resulting in the inhibition of methionine synthase. Nitrous oxide has greater
analgesic potency than other inhaled anesthetics
Dreaming while on nitrous is what? Overdose or normal
normal
How do you check to see if the oxygen (reserve) bag is okay?
It shouldn’t be that full or that collapsed
Device used in evaluation of N20?
Pulse oximeter (measure amount of O2 in blood)
The correct total liter flow of nitrous oxide-oxygen is determined by
the amount necessary to keep the reservoir bag 1/3 to 2/3 full.
Nitrous oxide: Total flow rate
4-6 L per min
Max amount of Nitrous Oxide for a kid
a. 40 %
b. 50%
c. 70%
50%
70 for adult
Nitrous for pedo pt is at 50%, what we do?
We stop giving it.
Nitrous safety switch happens at what percent?
70%
Abuse of nitrous oxide it results in
peripheral neuropathy.
Why is nitrous oxide used on children?
Alleviate anxiety
Child with fear is best treated with:
nitrous oxide
What is an adverse effect of nitrous?
Nausea
Most common side effect of nitrous oxide?
Nausea
If patient does not have 100% oxygen after nitrous oxide?
Diffusion hypoxia
QUESTION: Nitrous should not be given in ____ trimester of pregnancy
1st
What trimester is nitrous use contraindicated in?
first
When is nitrous contraindicated for a child?
upper respiratory tract infection
When is nitrous contraindicated? Asthma or COPD
COPD
local anesthetic chemical structure
- Lipophilic group (ex. aromatic ring) = facilitates penetration into nerve sheath
- Intermediate chain (ester or amide link) = ester is more prone to hydrolysis so shorter action duration
- Hydrophilic 20 or 30 amino terminus = weak base that is either charge or uncharged
mnemonic to identify ester vs amide anesthetics
esters: no “i” before “caine”
like procaine, benzocaine etc
amides: yes “i” before “caine”
like lidocaine, mepivacaine etc
what do onset and duration depend on
dose and lipid solubility (potency)
increased potency with increased lipid solubility because rapid penetration and duration
pKa related to onset
lower pKa faster onset
which nerver fibers blocked first
A-δ & C fibers (conduct pain sensation) are blocked w/ lower [LA] than Aα motor fibers.
what does duration of action of local anesthtic depend on
- diffusion away from site of action – MAJOR FACTOR, depends on vascularity of tissue surrounding the nerve.
- protein binding: high protein bound –> prolong duration (ex. bupivacaine, etidocaine, tetracaine)
max dose of 2% lido with 1:100,000 epi
7mg/kg for adult | 4.4mg/kg for pediatrics
Max dose of epi for cardio pt:
0.04mg (2 carps of 1:100k epi, 1 carp of 1:50k epi , or 4 carp of 1:200k epi max = 4 carps)
Max dose of epi for healthy person:
0.2 mg (8 carp of 1:100k epi)
Know where L.A. metabolized?
Amides made in P450 enzyme of liver. Esters in pseudocholinesterase of plasma.
Mode of action of Lidocaine:
Block sodium channels
What is the mechanism of local anesthetics?
Blocks Na channels intracellularly
QUESTION: Mech of action of local anes on nerve axon –
decreases sodium uptake through Na+ axon channels
QUESTION: What is the primary reason for putting epi in LA?
to slow its removal from the site. PROLONG DURATION OF ACTION
Adding a vasoconstrictor to local anesthesia does all the following EXCEPT:
a. Decreases rate of absorption
b. Increases duration of action
c. Minimizes toxicity and helps homeostasis
d. all of above
d. all of above
Local anesthetics broken down by what:
biotransformation
QUESTION: Patient got LA injection & started breathing fast, hands and finger are moving, heart rate is up -
You injected into a blood vessel
Patient get LA injection, he started to breathe a lot, HR goes up, due to what?
cardiovascular response to vasoconstrictor
HTN pt. you just gave 4 carpules of 2% xylocaine with 1:100k epi. BP went up to 200/100. what’s possible mechanism/cause?
Due
to vasoconstrictor injected into venous system.
You gave local anesthetic, BP went down to 100/50 and HR went down too, what could it be due to?
Syncope
QUESTION: Infection around a tooth & can’t numb patient, why?
Infection reduces the free base amount of anesthetic (lowers pH)
Why doesn’t anesthesia work when you have an infection?
Decreased pH (acidic environment) leads to more ionized form (less nonionized)
Abscess, give LA, decreased in effect, why?
LA is unstable in low pH or LA is in ionized form, needs to be in free base form or
unionized form to cross membranes
Where do you inject if infiltration in the area will not be able to avoid the infection?
Block
As LA becomes more ionized, it becomes more
water soluble.
If you have pain, what would be the hardest to anesthetize?
a. Irreversible pulpitis and maxillary
b. Irreversible pulpitis and mandibular
c. Necrotic pulp and maxillary
d. Necrotic pulp and mandibular
b. Irreversible pulpitis and mandibular
- When irreversible pulpitis, the teeth that are hard to anesthetize are the mandibular molars > mandibular premolars > maxillary
molars & premolars > mandibular anterior teeth. - fewest problems w/ the maxillary anterior teeth
The pKA of an anesthetic will affect what. Metabolism, potency, peak effect, onset
onset
When do you know that is it a non-odontogenic pain?
When pain is not relieved with LA
How do you treat lidocaine overdose?
Diazepam
What slows the metabolism of lidocaine?
Propranolol
- stays in system longer because propranolol slows down heart –> slower blood delivery to liver –> metabolism of lidocaine is slower –>
stays in system longer)
How much epi for a cardio pt?
- 04mg
Lidocaine is not metabolized
in plasma (but in liver)
QUESTION: Which of the following anesthetic can be used as topical? butamben, dibucaine, lidocaine, oxybuprocaine, pramoxine,
proparacaine, proxymetacaine, and tetracaine
lidocaine
What anesthesia do you give IV for ventricular arrhythmia?
a. Quinidine
b. Lidocaine
Lidocaine
Cocaine overdose symptoms? pinpoint pupils or mydriasis
mydriasis
Which LA causes vasoconstriction?
Cocaine
- Cocaine has intrinsic vasoconstrictive activity
Pt is in rehab for cocaine, what you prescribe for pain?
ADVIL
Prilocaine causes
methemoglobinemia (when given over 500mg)
- Symptoms of methemoglobinemia: cyanosis, headache, confusion, weakness, chest pain
because toluidine
Administer 600 mg of prilocaine. What possible result?
Methemoglobinemia above 500mg
- can be treated with methylene blue
Levonordefrin is added to certain cartridges containing mepivacaine to: increase .
vasoconstriction
QUESTION: best LA to use w/o vasoconstrictor:
a. pro
b. benzo
c. lido
d. articaine
e. mepivicane
mepivicane (carbo)
Articaine(septocaine): metabolized in
blood first.
- unique bc it is an Amide, but has an ester group that is metabolized in the bloodstream
Articaine - conjugated at
blood Stream by esterase (unlike other amides, it metabolized in blood stream).
bc has an ester group in addition to amide!
Anesthesia of facial nerve will cause all except:
• instant muscular dysfunction in half the face
• excessive salivation
• inability to smile
• inability to close eye
• corner of mouth will droop
• excessive salivation
Which drug is LEAST likely to result in an allergy reaction?
a. epinephrine
b. procaine
c. bisulfite
d. lidocaine
a. epinephrine
What is the best predictor for pulpal anesthesia? Concentration of anesthetic Volume of anesthetic Back pressure Type of anesthetic
Back pressure
- back pressure anesthesia stops hemorrhage, anesthesia after 30 sec, patient doesn’t feel it
which roots of M1 does PSA block
not MB
QUESTION: Which order will sensation disappear?
- pain, 2. temp, 3. touch, 4. pressure
PSA numbs palatal tissue
false
The dentist is performing a block of the maxillary division of the trigeminal nerve into which anatomical area must the local
anesthetic solution be deposited or diffused?
a. pterygomandibular space
b. pterygopalatine space
c. retropharyngeal space
d. retrobulbar space
e. canine space
b. pterygopalatine space
For a patient with multiple sclerosis
A. epinephrine is contraindicated in local anesthetic.
B. the amount of anesthetic needed for a given procedure is less than for a normal patient.
C. the amount of anesthetic needed for a given procedure is more than for a normal patient.
D. a single cartridge of anesthetic will most likely not last as long as it would for a normal patient.
A. epinephrine is contraindicated in local anesthetic.
use mepivacaine (levonoderfin)
Lidocaine calculation: a cartridge that contains 1.8 ml of solution at a 2% (20mg/ml) lidocaine concentration, how much drug?
36
mg/ml of drug (20 mg/ml X 1.8 ml/cart. = 36 mg/ml)
Lidocaine calculation: 2% lidocaine or 1:100,000. how much anesthetic is in a cartridge?
36mg
Max dosage of 2% lidocaine for a kid in mg/kg:
- 4 mg/kg
- MAXIMUM allowable dose of 2% lidocaine with 1: 100,000 EPI - 7mg/kg for adult’s 4.4mg/Kg for Pedo
Numb the kid, how many hours is the soft tissue numb?
3 hrs.
Kids have
higher pulse, basal metabolic activity & higher respiratory rate but lower BP
Typical pulse for a 4-year-old is
110 (12 yr. old is 75, adult is 70)
20 kg child how many mgs of lidocaine can you give:
88mg
- Max lidocaine w/ epi for kids = 4.4 mg/kg X 20 kg = 88 mg
Kid is 16kg, How many mg max amount of lidocaine?
70mg
88 lbs. (40kg) child patient is given 2 cartridges 1.8 ml each of 2% lidocaine with 1: 100,000 epinephrine. Approximate what % of
maximum dosage allowed for this patient was administered?
a. 10%
b. 20%
c. 40%
d. 60%
- 88lbs2.2 kg/lb. = 40 kg. 40kg4.4mg/kg (max dose for lido) = 176mg = max dose for this patient; 36 mg x 2 cartridges = 72 mg injected
- -> 72mg injected/176mg = 40%
50 lb. patient given 5 carps of 2% lido with 1:100k epi. During procedure 20 min later, he started twitching his arms and legs & went
unconscious (convulses), why? Overdose of lidocaine, overdose of the epi, allergy
Overdose of lidocaine
overdose of epi would give HTN
Maximum recommended dosage of lidocaine HCl injected subcutaneously (not IV) when combined with 1:1,00,000 epinephrine is?
a. 100 mg
b. 300 mg
c. 500 mg
d. 1 gram
c. 500 mg
- 6ml of 4% prilocaine contain how much anesthesia?
a. 72 mg
b. 80 mg
c. 144 mg
d. 360 mg
c. 144 mg
- 4% prilocaine = 40 mg/mL; 3.6 mL x 40 mg/mL = 144 mg
How many carps of 4% [X] anesthetic should be given if maximum amount that you want to give is 600mg of drug?
- approximately 8 carps (go over calculation) - 4% = 40 mg/mL = 600/40 = 15 mL/1.8ml (in 1 carp) = 8 carps
The maximum allowable adult dose of mepivacaine is 300 mg. How many milliliters of 2% mepivacaine should be injected to attain the maximal dosage in an adult patient? a. 5 b. 10 c. 15 d. 20 e. 25
c. 15
- 2% mepivicaine = 20mg/ml; 300mg/20 = 15 mL
Maximum dose of mepivicaine?
400mg
- Maximum dosage: prilocaine (600 mg) > articaine + lidocaine (500 mg) > Bupivacaine (90 mg)
A recently-introduced local anesthetic agent is claimed by the manufacturer to be several times as potent as procaine. The product
is available in 0.05% buffered aqueous solution in 1.8 ml. cartridge. The maximum amount recommended for dental anesthesia over a 4-hour
period is 30 mg. This amount is contained in approximately how many cartridges?
a. 1-9
b. 10-18
c. 19-27
d. 28-36
e. Greater than 36
- 0.05% = 0.5 mg/mL = 30m mg/ (0.5 mg/mL) = 60 mL/ (1.8 mL/carp) = 33.3 carp
What determines max. dose for anesthetic for a child?
Weight
A 26-month old child w/ 12 carious teeth. How to treat?
a. General Anesthesia
b. Oral sedation
c. Nitrous oxide
d. local anesthesia
a. General Anesthesia
QUESTION: Kid under general anesthesia:
give chloral hydrate and midazolam
QUESTION: Pt is under oral sedation. You should monitor everything except?
- Respiration
- Oxygen saturation level
- Electo cardiogram
- Skin and oral mucosa color
• Electo cardiogram
1 cause for problems during IV sedation?
Hypoxia
A 77 years old female 110 lbs. weight requires removal of mandibular teeth under local anesthesia. She is apprehensive. The
appropriate dose of IV diazepam to sedate her?
a. 5 mg
b. 10 mg
c. 15 mg
d. 20 mg
b. 10 mg
- 2mg for midazolam IV, 10 mg diazepam IV
Pt goes home from elective orthognathic sx and in 24hrs, without sign of inflam or edema, but a fever of 102 F-
Atelectasia (or pneumotosis – depending on answers)
- Atelectasia and pneumotosis = most common cause of fever within 24 hour of GA
Pre-med with odontogenic infection:
- Amox for SBE prophylaxis
- Penicillin for odontogenic infections
- Tetracycline for periodontal infections (better penetration, stays in bone tissue longer)
Which procedure least likely to produce bacteremia? extraction, non-surgical endo, oral prophylaxis
oral prophylaxis
Condition that DOES NOT require antibiotic prophylaxis
o Prosthetic heart valve
o Rheumatic heart valve
o Congenital heart formations
o Cardiac pacemaker
o Cardiac pacemaker
Indication for antibiotic prophylaxis:
artificial heart valve, previous IE, congenital heart (valvular) defect, total joint replacement w/ co-morbidity
Prophylactic treatment for prosthetic heart valves –
premedication required
Prophylactic treatment for Pacemaker –
No premedication required
- Just stay away from ultrasonic and electric testing/ electrocautery
What is the pre-medication dosage for child 44 lbs.?
1-gram amoxicillin 1 hour prior Tx.
- 44 lbs. = 20Kg X 50mg/Kg = 1000mg = 1g Amoxicillin
Pt w/ mitral valve prolapse w/ regurgitation –
don’t premedicate
(Patient’s medical tab say he is allergic to Amoxicillin), He needs to be premediated, what do you prescribe?
Clindamycin, 600mg
1hr before the dude shows up for the appointment.
Man has accident and pin placed in arm. What antibiotic prophylaxis does he need?
None
QUESTION: Pt w/ total knee replacement but was taking Amoxicillin for a while; how do you premedicate?
NO (or MED CONSULT)
Pt had hip replacement 10 years ago, what do you use to premedicate?
No premedication needed
Pt needs antibiotic prophylaxis. He is taking penicillin already, what do you give him?
Clindamycin
Regular premedication case:
Give amoxicillin 2g 1hr b4
What is recommended prophylaxis for pt that can’t take penicillin?
Clindamycin
why premedicate?
benefits of premedication outweigh potential harm associated with penicillin
Endocarditis definition:
inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves (native or
prosthetic valves)
QUESTION: Infectious Endocarditis pre-medications definition?
For patients who has cardiovascular problems and are at risk of infection over
their lifetime.
When is it appropriate to prescribe antibiotic prophylaxis in patient with previous infective endocarditis?
if consequence of
potential infection is detrimental to life
Which of these procedures pose a risk for Infective Endocarditis? • Primary teeth shedding • RCT • Some sort of surgery • IA injection
• Some sort of surgery
Guideline of antibiotic prophylaxis, especially for kids -
for kids, Amox is 50mg/kg and Clinda is 20 mg/kg
QUESTION: Know the doses for someone that is allergic to penicillin, what you can give them?
Clarithromycin 500mg
If a patient is allergic to Ampicillin, what else can you premedicate with?
Clindamycin 600mg 1, Cephalexin 2g, Azithromycin 500
mg, or Clarithromycin 500 mg all 1-hr before.
Most bacteriostatic meds works by:
Inhibiting protein synthesis
Broad spectrum antibiotics like tetracycline:
increase superinfection and resistance.
broad spectrum antibiotics –>
increase superinfection (infxn by candidiasis) and resistance.
Why don’t we use broad spectrum antibiotics?
Produce resistant bacteria
If you increase spectrum of bacteria, it leads to
more infections
QUESTION: Antibiotics are least useful for tx of this periodontal conditions: LAP, NUG, chronic periodontitis
chronic periodontitis
Antibiotic metabolism is affected by chronic tx with what drugs? Benzos, barbs, SSRI, TCA
Benzos
Pt is taking an antibiotic, which is metabolized in the liver. Metabolism of this antibiotic is decreased by which drug?
a. TCA
b. SSRI
c. phenothiazine
d. diazepam
diazepam
You give antibiotics through IV, patient experience sudden allergic reaction, what’s the FIRST thing you do?
remove the IV line.
Penicillin, why is this so good to give as an antibiotic?
Low toxicity, cheap
Keflex (cephalexin) mechanism is closely related to what
penicillin
What is the effect of Penicillin and Cephalosporin’s
(cell wall synthesis) via beta lactam ring
Transpeptidase enzyme is inhibited by
penicillin
- Transpeptidase, a bacterial enzyme that cross-links the peptidoglycan chains to form rigid cell walls
Which of the following penicillin would be used to treat a Pseudomonas infection? Nafcillin (Unipen) Amoxicillin (Amoxil) Benzedrine penicillin (Bicillin) Phenoxymethyl penicillin (Pen-Vee K) Ticarcillin (Thar)
- Ticarcillin is a carboxypenicillin. Its main use is for the treatment of Gram-negative bacteria, particularly Pseudomonas aeruginosa.
Why do penicillins have decreased effectiveness in abscess?
hyaluronidase, pen unable to reach organism
With cyst, why doesn’t penicillin work well?
b/c can’t penetrate cyst barrier
1 dental antibiotic for an infection within 24hrs is
Pen VK 1gm booster and 500mg q6h
Penicillin V potassium is a slow-onset antibiotic, bacteriocidal against gram (+) cocci & major pathogen of mixed anaerobic infections. In
the absence of an allergic reaction, penicillin VK is the drug of choice in treating dental infections.
if early (first 3 days of infection): penicillin VK, amoxicillin, clindamycin, cephalexin
For an infection:
give PenVK 500mg à give 1g at once and then 500 mg every 6 hours (7 days)
What antibiotic used for endo, pulpal involvement?
PEN VK (yes it actually says VK together)
cephalosporin spectrum vs penicillin spectrum
cephalosporin is narrower
cephalosporin is a beta lactam antibiotic, bactericidal, 1st generation, more concentrated on gram (+), more resistant to penicillinase
broadest abx effect
chlortetracycline
Tetracycline mechanism of action:
protein synthesis inhibitor (30s), bacteriostatic
How does tetracycline work?
Block activity of collagenase, bind to 30S (block AA linked tRNA)
- Tetracycline is usually not used because they cause yeast infections, as well opportunistic infect.
Doxycycline
- Doxycycline reversibly binds to the 30 S ribosomal subunits and possibly the 50S ribosomal subunit(s), blocking the binding of aminoacyl
tRNA to the mRNA and inhibiting bacterial protein synthesis. - It’s a tetracycline, treats malaria
20 mg of doxycycline action in periodontal dressing
20 mg = no anti-bacterial effect but it inhibits collagenase
QUESTION: Which antibiotic is anti-microbial and anti-collagenlyctic? clindamycin, doxycycline, metronidazole, amoxicillin
doxycycline
Tetracycline does not do one of the following: reduce host response reduce bacterial infection reduce host collagenase decrease gingival crevicular fluid flow
decrease gingival crevicular fluid flow
Minocycline & Doxycycline:
Both increase GCF secretion, both released in GCF (Gingival crevicular fluid)
- tetracycline is more concentrated in GCF more than in blood
Mechanism of action of Minocycline in the Arestin:
decrease collagenases activity
- Minocycline, another tetracycline antibiotic, has also been shown to inhibit MMP activity.
What drug has the highest concentration in crevicular fluid?
Tetracycline
Which one of the following drug is chelated with Ca++?
Tetracycline
what reduces absorption of tetracycline
milk and antacids
Don’t take iron supplements, multivitamins, calcium supplements, antacids, or laxatives within 2 hours before or after taking tetracycline.
What is most affected by tetracycline? Enamel or Dentin
Dentin, causes intrinsic stain
What age are you most likely get infection that resulted in enamel hypoplasia or tetracycline staining?
before 4 months in utero for
primary; birth for permanent
What medication do you not give to lactating female?
Codeine and tetracycline
Child comes in with an oral infection and is NOT allergic to Pen. What do you prescribe?
a. Penicillin
b. Amoxicillin
c. Tetracycline
Amoxicillin
What happens when you have penicillin and decide to prescribe tetracycline with it?
Tetracycline will decrease the efficacy of
Penicillin.
- Don’t do it. Tetracline is bacteriostatic whereas penicillin is bacteriocidal. The two mechanisms of action (CIDAL+STATIC) cancel each other
out because when you need bacterial growth to actually use penicillin, but you don’t have that growth when you prescribe Tetracycline.
QUESTION: Penicillin and erythromycin taken together cause:
•summation
•potentiation
•antagonists
antagonists
1 side-effect of erythromycin is?
Stomach upset.
In lethal doses of erythromycin, what do you see? Hepatocellular, GI damage
GI damage
Myasthenia gravis patient, what can’t you give them? Erythromycin, clarithromycin, penicillin or Impemene
Erythromycin
If you have maxillary sinusitis, what antibiotic would you give?
Amoxicillin with clavulanic Acid (Augmentin)
- Clavulanic acid increases spectrum of action & restored efficacy against amoxicillin-resistant bacteria that produce β-lactamase.
What the clavulanic acid do when is mixed with amoxicillin (Augmentin)?
decrease sensitivity from b-lactamase
clavulanic acid in amoxicillin -
prevents beta lactam degradation by beta lactamase producing bacteria
Augmentin:
blocks the action of penicillinase, penicillinase resistant
Metronidazole -
prescribed in necrotizing ulcerative gingivitis (NUG) or aggressive periodontitis
- metronidazole is contraindicated in patients on alcohol causing disulfiram type of reaction
- has red urine
Antibiotic against only anaerobes parasites (protozoa)?
Metronidazole
Clostridium difficile (colon inflammation) is treated with
metronidazole. Unless pt is pregnant or breastfeeding, then use
vancomycin.
QUESTION: Best treatment of localized aggressive periodontitis:
tetracycline, Doxycycline
Which antibiotic is NOT inhibit cell wall synthesis?
- amoxicillin
- vancomycin
- azithromycin
azithromycin (this inhibits protein synthesis)
QUESTION: Gentamycin (aminoglycosides) - May cause
auditory nerve deafness
aminoglycosides: toxicity
ototoxicity and nephro
Pseudomonas colitis:
c. difficile and clindamycin
Which of the following describes clindamycin?
a. inhibits cell wall synthesis
b. does not penetrate well into bony tissue
c. it usually given in combination with erythromycin
d. is effective against gram-negative bacteria only
e. is effective against most anaerobes
e. is effective against most anaerobes
Which of the following describes ciprofloxacin (Cipro®)?
Inhibits cell wall synthesis.
Effective against Pseudomonas aeruginosa.
Effective only against anaerobic bacteria.
An antibiotic-of-choice for treating otitis media in young children.
Effective against oral anaerobes.
Effective against Pseudomonas aeruginosa.
QUESTION: Chloramphenicol (antibiotic) adverse effect
aplastic anemia
Anti-cancer drugs are least likely to cause what? Ulcers, thromboembolism
thromboembolism
What’s an adverse effect of a drug that you can’t mix with antibiotics?
Methotrexate because it won’t clear out of the system,
specifically with amoxicillin.
- Penicillin can decrease elimination of methotrexate (cancer drug), increasing risk of methotrexate toxicity, which can cause seizures.
Methotrexate (MTX) is an:
antimetabolite and antifolate drug. Used for tx of cancer, autoimmune diseases, ectopic
pregnancy, and for the induction of abortions. It inhibits folic acid metabolism.
QUESTION: Which drug will be used to treat an overdose of methotrexate?
Leucovorin
- Methotrexate toxicity effects can be reversed by folic acid (leukovorin)
Which medication for anticancer works on folate synthesis/ prevents folic acids synthesis/prevents folic acid production:
methotrexate
Methotrexate is an anti-cancer drug that inhibits
folate reductase
Drug agonist of folic acid?
Sulfa, Trimethoprim, Methotrexate
Anti-cancer drug (Mechlorethamine), that was an alkylating agent, what was it effect?
Neurotoxic
Alkalizing anti-cancer drug called procarbazine causes:
Hepatotoxicity
- Inhibits CYP450, increased effect of barbiturates, phenothiazenes, and narcotics. Has monoamine oxidase inhibition properties (MAOI),
and should not be taken with most antidepressants and certain migraine medications.
Non-alkylating anti-cancer side effect?
myelosuppression (BONE MARROW SUPPRESSION)
amantadiene is for what
influenza A
tamiflu, oseltamivirm zanamivir is tx for what
influenza A and B
acyclovir
herpes 1, 2, VZV, EBV
gancyclovir
CMV
ribavirin
Hep C and RSV
CMV tx
gancyclovir
Hep C tx
ribavirin
Picture of lesion at corner of mouth, patient says it
comes and goes now and then, what type of infection would you
suspect?
Viral
Amantadine is an anti-viral and anti-parkinsonian or
anti-TB and its anti-viral.
anti-viral and anti-parkinsonian
What anti-viral is used to for all the these: HSV, VZV, CMV?
Valacyclovir
and acyclovir
What virus causes postherpetic neuralgia?
VZV
Acyclovir has selective toxicity mechanism of action b/c:
inhibits viral mRNA
inhibits cellular mRNA in infected cells
only phosphorylated and activated in infected cells
only phosphorylated and activated in infected cells
- Inhibits mRNA, doesn’t work on DNA
HIV patient with sinusitis due to what?
Mucormycosis
Most reliable measure of HIV progression? CD4 count, viral load
CD4 count
CD4 count and T-cell count for HIV symptoms: pt had HIV
CD4 less than 200
Pt has viral load of 100,000:
pt has high virus load and prone to infection
Pt’s viral load was 100,000, and T cell count was 50. What is the right statement?
Pt’s T cell count is too low
- Healthy T-cell count: 500-1500 units/ml
Which of the following is not a risk of oral cancer
a. Tobacco
b. Alcohol
c. HPV
d. HIV
HIV
Which of the following agents is used for HIV infection?
a. amantadine
b. acyclovir
c. zidovudine
d. ribavirin
e. isoniazid
c. zidovudine (also called AZT)
a. amantadine (Parkinson’s and influenza A)
b. acyclovir (Herpes)
c. zidovudine (also called AZT)
d. ribavirin (Hep C; also RSV)
e. isoniazid (TB; also streptomycin)
What oral manifestation is seen in children with HIV?
Candidiasis
Fungal agent for HIV:
Fluconazole or ketoconazole
Candidiasis & HIV, what do you give systemic or topical anti-fungal?
Nystatin
Azoles:
anti-fungal, inhibit lanosterol conversion to ergosterol
Polyenes
anti-fungal, bind to ergosterol on cell membrane and create a pore/transmembrane channel
o Includes Amphotericin B
Topical anti-fungal:
Mycelex (clotrimazole), Nystatin, Ketoconazole
Systemic anti-fungal:
Fluconazole (Diflucan), Amphotericin B, Ketoconazole
- Know “FAK”
Nystatin how to :
“swish & swallow”
antifungal troches
clotrimazole, 5/day x 14; DO NOT CHEW
systemic antifungals use
fluco - 100mg.day
Medication for angular chelitis:
nystatin
Oral anti-fungal infection:
Nystatin
- Clotrimazole(Mycelex) and Nystatin are oral anti-fungals
Griseofulvin:
used for athlete’s foot.
- treat fungal infections such as ringworm, “jock itch,” and athlete’s foot.
Clotrimazole mechanism of action:
Alter the enzyme for synthesis of ergosterol, which alters cell membrane permeability
Mechanism of miconazole (antifungal):
inhibits the synthesis of ergosterol a critical component of the cell membrane
Best topical antifungal?
Mycelex