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Pharmacology I · Exam 1 · Class of 2028

Contraindications & Must-Know Warnings

Every contraindication, prohibition and named reaction in the three Exam 1 decks, in one place. 71 entries, each citing the slide it came from. Built after Dr. McInnis’s email that students over-study mechanism and under-study indications, patient education, side effects and contraindications.

Contraindicated — The deck uses the word contraindicated.Black box — The deck says black box warning.Avoid / do not use — The deck says avoid, do not use, cannot use, or teratogenic.Named reaction — A named syndrome or reaction — bold and underlined in the tables.Caution — A stated caution, monitoring need or major adverse effect — not worded as a contraindication.Safe exception — The deck says this one can be used where the class cannot — the flip side of a contraindication.
The tiers are not interchangeable, and that is the point. These decks are uneven: only 4 statements are actually worded “contraindicated”, one is a black box warning, and 10 say avoid / do not use / teratogenic. Everything else is a stated caution or a major adverse effect. Nothing here has been promoted a tier above what the slide says — if a row is marked Caution, the deck did not call it a contraindication, however much it sounds like one.
Two things this reference deliberately does NOT contain. 1. Dosages. Dr. Wood said drug dosages are not tested, so none are reproduced here. 2. Any race-based contraindication. All 310 slides were searched: there is no contraindication keyed to race or ethnicity anywhere in these three decks. If a question offers one, it is not from this material. (Race does appear as a risk factor for glaucoma — but that is the CMS ophthalmology deck, a different exam.) 3. Streptogramins. The Lecture 1 objectives slide names the class, but the deck contains no streptogramin slide at all — no drug, no contraindication. Nothing has been invented to fill that gap.
Beta-lactamsVancomycinProtein synthesis inhibitorsFluoroquinolonesOther antibacterialsAntifungalsAntivirals and anthelminthicsDermatology medicationsAutonomic — cholinergicAutonomic — adrenergic

The named reactions learn these by name

These are the ones a question can name directly — “a patient develops flushing of the head and neck during an infusion” is asking for one specific drug. Every named reaction on this page is bold and underlined wherever it appears.
Drug or classWhat it saysSource
Carbapenems
imipenem, meropenem, ertapenem, doripenem
Monitor renal and hepatic function, full blood count for bleeding, signs of anaphylaxis — and SEIZURES, specifically with imipenem. That pairing is the one carbapenem fact most likely to be asked.L1
slide 44
VancomycinInfusion-related reaction — “Red Man Syndrome”, with fever, chills and phlebitis. The deck also titles a slide “Vancomycin Infusion Syndrome”. It is an infusion-rate problem, which is why the drug is infused over 60 minutes.L1
slide 51
Macrolides
erythromycin, clarithromycin, azithromycin
QT prolongation and Torsades de pointes — worse in combination with class Ia and III antiarrhythmics and with electrolyte abnormalities.L1
slide 57
Fluoroquinolones
ciprofloxacin, levofloxacin, moxifloxacin
Tendonitis and Achilles tendon rupture. Caution if under 18 years old. Also peripheral neuropathy and central nervous system toxicity — dizziness, insomnia, somnolence.L1
slide 79
Fluoroquinolones
ciprofloxacin, levofloxacin, moxifloxacin
QT prolongation and Torsades de Pointes. Photosensitivity, and they complex with cations — iron, antacids, multivitamins, calcium and dairy.L1
slide 79
Trimethoprim / sulfamethoxazole
Septra, Bactrim
Stevens-Johnson syndrome and toxic epidermal necrolysis. Blood dyscrasias — thrombocytopenia, agranulocytosis, megaloblastic anemia. Hepatotoxicity and hyperbilirubinemia.L1
slide 85
Metronidazole
Flagyl
Disulfiram-like reaction with ethanol. The single most testable fact about this drug — counsel the patient not to drink.L1
slide 86
Linezolid
Zyvox
Serotonin syndrome with SSRIs, tyramine-containing foods and pseudoephedrine. Also thrombocytopenia.L1
slide 71
Albendazole, mebendazole
Albenza, Emverm
Very well tolerated, but rash including Stevens-Johnson syndrome and toxic epidermal necrolysis is described.L1
slide 115
Atropine and antimuscarinicsThe anticholinergic toxidrome: mad as a hatter (sedation, anxiety, hallucinations, seizures), blind as a bat (mydriasis, blurry vision), red as a beet (flushing), dry as a bone (decreased secretions), hot as Hades (hyperthermia), plus constipation, urinary retention and tachycardia.L3
slide 50
SuccinylcholineMalignant hyperthermia with halothane in genetically susceptible people — muscular rigidity, metabolic acidosis, tachycardia and hyperpyrexia. Treat by rapid cooling and dantrolene (Dantrium).L3
slide 70
Clonidine
Catapres
Rebound hypertension with abrupt discontinuance. Also lethargy, sedation, constipation and xerostomia.L3
slide 97
Alpha-1 blockers
prazosin, terazosin, doxazosin, tamsulosin, alfuzosin
“First-dose” syncope. Also dizziness, lack of energy, nasal congestion, headache, drowsiness and orthostatic hypotension.L3
slide 111
PhenoxybenzamineEpinephrine reversal — it blocks the alpha vasoconstriction of epinephrine but not its beta vasodilation, so blood pressure falls. Block is irreversible; the body must synthesize new receptors, taking at least 24 hours.L3
slide 109
Propranolol
non-selective beta blocker
Arrhythmias if stopped abruptly, from up-regulation of beta receptors — never stop a beta blocker suddenly. Also central effects: depression, hallucinations, vivid dreams and nightmares.L3
slide 117

Pregnancy, breastfeeding and teratogenicity the highest-yield group

Three different strengths sit in this one table, and a question can turn on which one a drug gets. Isotretinoin is an absolute contraindication in pregnancy and breastfeeding, with men told to avoid it too. Itraconazole is flagged teratogenic outright, while fluconazole and voriconazole are only “teratogenic in animals”. Everything else is worded as avoid. Read the wording, not just the drug name.

Related but not the same thing: aminopenicillins reduce the effectiveness of oral contraceptives — that is a risk of a pregnancy happening, not a risk to a fetus, so it sits under beta-lactams rather than here.
Drug or classWhat it saysSource
Tetracyclines
tetracycline, doxycycline, minocycline
Avoid in the 2nd and 3rd trimester of pregnancy. Also photosensitivity, and they chelate with cations — iron, calcium and dairy block absorption.L1
slide 63
Tetracyclines — for acne
Lecture 2 restates it harder
Contraindicated in children under 8 years and in pregnant women. Lecture 2 words this as an outright contraindication where Lecture 1 says “avoid”.L2
slide 28
Itraconazole
Sporanox
Teratogenic. Substrate for and inhibitor of CYP3A4.L1
slide 104
Fluconazole
Diflucan
Teratogenic in animals. Inhibits CYP3A4 and CYP2A4.L1
slide 106
Voriconazole
Vfend
Teratogenic in animals. Visual effects in 30%, plus liver and renal effects. The intravenous vehicle cyclodextrin accumulates in renal failure.L1
slide 107
Isotretinoin
Accutane
CONTRAINDICATED in pregnancy and breastfeeding — men should avoid as well. Enrollment in iPledge is required. Monitor for signs of developing depression and for raised serum lipids.L2
slide 27
Topical retinoids
tretinoin, adapalene, tazarotene
Avoid during pregnancy. Photosensitivity and severe sunburn. Benzoyl peroxide inactivates tretinoin, and tretinoin is photolabile so it is applied nightly.L2
slide 24

Age-specific warnings the numbers to memorize

Three numbers carry this section: 30 days (ceftriaxone in the newborn), 8 years (tetracyclines — teeth and skeletal growth) and 18 years (fluoroquinolones — tendon). If a stem gives you a child’s age, it is usually testing one of those three. The last row is not an age limit but a pediatric-only consequence: topical steroids can retard growth.
Drug or classWhat it saysSource
Ceftriaxone
Rocephin
Cannot be used during the first 30 days of life. Cefotaxime is preferred in neonatal fever or sepsis. No dosage adjustment is needed in renal insufficiency.L1
slide 34
Tetracyclines
tetracycline, doxycycline, minocycline
Avoid under 8 years old — causes discoloration of teeth (doxycycline more than the others) and depression of skeletal growth.L1
slide 63
Tetracyclines — for acne
Lecture 2 restates it harder
Contraindicated in children under 8 years and in pregnant women. Lecture 2 words this as an outright contraindication where Lecture 1 says “avoid”.L2
slide 28
Fluoroquinolones
ciprofloxacin, levofloxacin, moxifloxacin
Tendonitis and Achilles tendon rupture. Caution if under 18 years old. Also peripheral neuropathy and central nervous system toxicity — dizziness, insomnia, somnolence.L1
slide 79
Topical corticosteroidsLocal: skin atrophy, acne, rosacea, allergic dermatitis. Systemic: adrenal suppression, infections, hyperglycemia, glaucoma, cataracts, and growth retardation in children. Risk rises with potency, duration, area covered and occlusiveness — ointment > cream > lotion.L2
slide 38

Beta-lactams Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
Aminopenicillins
amoxicillin, ampicillin
ContraindicatedContraindicated in patients allergic to penicillin, and in a patient with a past history of cholestatic jaundice or hepatic dysfunction.L1
slide 21
Aminopenicillins
amoxicillin, ampicillin
CautionReduces the effectiveness of oral contraceptives — use backup birth control. Prolongs prothrombin time with anticoagulants.L1
slide 20
Penicillins — classCautionAdverse reactions are hypersensitivity reaction, rash and diarrhea. Dosing is adjusted for renal function. Monitor renal and hepatic function and platelets.L1
slide 22
Cephalosporins — classCautionPenicillin cross-sensitivity of approximately less than 1% — the number to know when a stem gives you a penicillin-allergic patient.L1
slide 30
Ceftriaxone
Rocephin
Avoid / do not useCannot be used during the first 30 days of life. Cefotaxime is preferred in neonatal fever or sepsis. No dosage adjustment is needed in renal insufficiency.L1
slide 34
Carbapenems
imipenem, meropenem, ertapenem, doripenem
Named reactionMonitor renal and hepatic function, full blood count for bleeding, signs of anaphylaxis — and SEIZURES, specifically with imipenem. That pairing is the one carbapenem fact most likely to be asked.L1
slide 44
Aztreonam
monobactam
Safe exceptionThe exception worth memorizing: NO cross-reactivity with beta-lactams, so it can be used in truly penicillin-allergic patients.L1
slide 41

Vancomycin Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
VancomycinNamed reactionInfusion-related reaction — “Red Man Syndrome”, with fever, chills and phlebitis. The deck also titles a slide “Vancomycin Infusion Syndrome”. It is an infusion-rate problem, which is why the drug is infused over 60 minutes.L1
slide 51
VancomycinCautionMonitor for ototoxicity and nephrotoxicity, and follow renal clearance. Requires therapeutic drug monitoring — trough drawn 15–30 minutes before the next dose, around the 3rd or 4th dose.L1
slide 51

Protein synthesis inhibitors Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
Macrolides
erythromycin, clarithromycin, azithromycin
Named reactionQT prolongation and Torsades de pointes — worse in combination with class Ia and III antiarrhythmics and with electrolyte abnormalities.L1
slide 57
Macrolides
erythromycin, clarithromycin, azithromycin
CautionCholestatic hepatitis (rare, more with the estolate salt) and transient hearing loss with large intravenous doses or in renal insufficiency.L1
slide 57
Macrolides
erythromycin, clarithromycin, azithromycin
CautionCYP3A4 interaction raises levels of carbamazepine, cyclosporine, digoxin, midazolam and theophylline. Erythromycin > clarithromycin > azithromycin. Check the drug profile before prescribing.L1
slide 59
Tetracyclines
tetracycline, doxycycline, minocycline
Avoid / do not useAvoid under 8 years old — causes discoloration of teeth (doxycycline more than the others) and depression of skeletal growth.L1
slide 63
Tetracyclines
tetracycline, doxycycline, minocycline
Avoid / do not useAvoid in the 2nd and 3rd trimester of pregnancy. Also photosensitivity, and they chelate with cations — iron, calcium and dairy block absorption.L1
slide 63
Clindamycin
Cleocin
CautionClostridium difficile and pseudomembranous colitis — the reaction this drug is known for. Also rash, neutropenia and thrombocytopenia.L1
slide 81
Linezolid
Zyvox
Named reactionSerotonin syndrome with SSRIs, tyramine-containing foods and pseudoephedrine. Also thrombocytopenia.L1
slide 71
Aminoglycosides
gentamicin, tobramycin, amikacin
CautionRenal toxicity and ototoxicity — renally adjusted, and they require therapeutic drug monitoring with peak and trough levels.L1
slide 68

Fluoroquinolones Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
Fluoroquinolones
ciprofloxacin, levofloxacin, moxifloxacin
Named reactionTendonitis and Achilles tendon rupture. Caution if under 18 years old. Also peripheral neuropathy and central nervous system toxicity — dizziness, insomnia, somnolence.L1
slide 79
Fluoroquinolones
ciprofloxacin, levofloxacin, moxifloxacin
Named reactionQT prolongation and Torsades de Pointes. Photosensitivity, and they complex with cations — iron, antacids, multivitamins, calcium and dairy.L1
slide 79
Moxifloxacin
Avelox
Avoid / do not useDo not use for urinary tract infections — the one fluoroquinolone that does not cover them. It also has no pseudomonas coverage.L1
slide 78

Other antibacterials Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
Trimethoprim / sulfamethoxazole
Septra, Bactrim
Named reactionStevens-Johnson syndrome and toxic epidermal necrolysis. Blood dyscrasias — thrombocytopenia, agranulocytosis, megaloblastic anemia. Hepatotoxicity and hyperbilirubinemia.L1
slide 85
Trimethoprim / sulfamethoxazole
Septra, Bactrim
CautionRaises phenytoin, rifampin and digoxin levels; causes hypoglycemia with sulfonylureas; and significantly increases INR (international normalized ratio) with warfarin by inhibiting CYP2C9.L1
slide 85
Metronidazole
Flagyl
Named reactionDisulfiram-like reaction with ethanol. The single most testable fact about this drug — counsel the patient not to drink.L1
slide 86
Polymyxin B and Polymyxin E
colistin
Black boxBLACK BOX WARNINGS for nephrotoxicity, neurotoxicity and neuromuscular blockade.L1
slide 88

Antifungals Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
Echinocandins
caspofungin, micafungin, anidulafungin
CautionAdverse reactions: tachycardia, headache, insomnia, hypokalemia, hypomagnesemia and blood dyscrasias.L1
slide 109
Amphotericin BCautionFever and chills from interleukin-1 and tumor necrosis factor — pre-treat with paracetamol, antihistamines and corticosteroids. Infused over 4 hours; side effects limit treatment.L1
slide 98
Amphotericin BCautionElectrolyte abnormalities — hypokalemia and hypomagnesemia, hypotension, uremia in 80% with decreased filtration, and renal tubule damage — hydrate with normal saline.L1
slide 99
Itraconazole
Sporanox
Avoid / do not useTeratogenic. Substrate for and inhibitor of CYP3A4.L1
slide 104
Fluconazole
Diflucan
Avoid / do not useTeratogenic in animals. Inhibits CYP3A4 and CYP2A4.L1
slide 106
Voriconazole
Vfend
Avoid / do not useTeratogenic in animals. Visual effects in 30%, plus liver and renal effects. The intravenous vehicle cyclodextrin accumulates in renal failure.L1
slide 107
Posaconazole
Noxafil
CautionQT prolongation, fever, diarrhea, hypokalemia, hypomagnesemia and thrombocytopenia.L1
slide 105
KetoconazoleCautionInhibits CYP3A4 — significant drug interactions. Does not enter the central nervous system, and is now rarely used.L1
slide 103
Flucytosine
5-flucytosine, Ancobon
CautionBone marrow suppression and hepatotoxicity.L1
slide 101
GriseofulvinCautionInduces CYP1A2 and CYP2C9. Headache in 15%, mental confusion, fatigue and blurred vision. Absorption increases with a high-fat meal.L1
slide 111

Antivirals and anthelminthics Antibiotics, Antivirals & Antifungals

Drug or classTierWhat it saysSource
Acyclovir, valacyclovir
Zovirax, Valtrex
CautionCrystallizes in the renal tubule — maintain hydration and renal function. Central nervous system effects include seizures, delirium and tremor; also bone marrow suppression.L1
slide 123
Ganciclovir, valganciclovir
Cytovene, Valcyte
CautionNeutropenia in 15–40% and thrombocytopenia. 33% of patients must stop intravenous treatment because of side effects.L1
slide 125
Oseltamivir
Tamiflu
CautionRequires renal dose adjustment. Oral only.L1
slide 127
Albendazole, mebendazole
Albenza, Emverm
Named reactionVery well tolerated, but rash including Stevens-Johnson syndrome and toxic epidermal necrolysis is described.L1
slide 115

Dermatology medications Dermatology Medications

Drug or classTierWhat it saysSource
Allylamines
naftifine, terbinafine (Lamisil)
CautionThe deck records only local irritation — no systemic contraindication is given for this class.L2
slide 53
Tetracyclines — for acne
Lecture 2 restates it harder
ContraindicatedContraindicated in children under 8 years and in pregnant women. Lecture 2 words this as an outright contraindication where Lecture 1 says “avoid”.L2
slide 28
Isotretinoin
Accutane
ContraindicatedCONTRAINDICATED in pregnancy and breastfeeding — men should avoid as well. Enrollment in iPledge is required. Monitor for signs of developing depression and for raised serum lipids.L2
slide 27
Topical retinoids
tretinoin, adapalene, tazarotene
Avoid / do not useAvoid during pregnancy. Photosensitivity and severe sunburn. Benzoyl peroxide inactivates tretinoin, and tretinoin is photolabile so it is applied nightly.L2
slide 24
Topical corticosteroidsCautionLocal: skin atrophy, acne, rosacea, allergic dermatitis. Systemic: adrenal suppression, infections, hyperglycemia, glaucoma, cataracts, and growth retardation in children. Risk rises with potency, duration, area covered and occlusiveness — ointment > cream > lotion.L2
slide 38
Topical immunomodulators
tacrolimus (Protopic), pimecrolimus (Elidel)
Avoid / do not usePossible cancer risk. Avoid in patients with weakened immune systems. Second line after topical steroids; use a high-SPF (sun protection factor) sunscreen.L2
slide 43
Polymyxin B
topical
Avoid / do not useAvoid using on open wounds or denuded skin in high doses — risk of neurotoxicity and nephrotoxicity.L2
slide 48
Neomycin
topical aminoglycoside
CautionFrequently causes sensitization, and topical aminoglycosides can accumulate systemically.L2
slide 49
Benzoyl peroxideCautionCan bleach hair, clothes, and irritates skin and mucous membranes. Start at 2.5% once daily.L2
slide 21
Intralesional and oral corticosteroids
acne
CautionSystemic absorption can occur → adrenal suppression and local tissue atrophy. Oral courses need tapering to prevent flare-up.L2
slide 30

Autonomic — cholinergic ANS Pharmacology

Drug or classTierWhat it saysSource
Cholinergic agonists — class
bethanechol, carbachol, pilocarpine
CautionMuscarinic excess causes bronchospasm, decreased blood pressure, salivation, sweating, flushing, nausea, abdominal pain and diarrhea — which is why these are a problem in reactive airway disease.L3
slide 31
Acetylcholinesterase inhibitors
neostigmine, pyridostigmine
CautionSame muscarinic burden — salivation, flushing, decreased blood pressure, nausea, abdominal pain, diarrhea and bronchospasm.L3
slide 38
Physostigmine
Antilirium
CautionConvulsions at high doses, bradycardia, decreased cardiac output, and paralysis of skeletal muscle from acetylcholine accumulation.L3
slide 37
Organophosphate poisoning
irreversible AChE inhibitors
CautionPralidoxime (Protopam) reactivates inhibited acetylcholinesterase — but it does not penetrate the central nervous system and cannot overcome reversible inhibitors such as physostigmine.L3
slide 42
Atropine and antimuscarinicsNamed reactionThe anticholinergic toxidrome: mad as a hatter (sedation, anxiety, hallucinations, seizures), blind as a bat (mydriasis, blurry vision), red as a beet (flushing), dry as a bone (decreased secretions), hot as Hades (hyperthermia), plus constipation, urinary retention and tachycardia.L3
slide 50
AtropineCautionAdverse effects: dry mouth, blurred vision, “sandy eyes”, urinary retention, constipation, and central effects — restlessness, confusion, hallucinations, delirium. Dose-dependent heart rate: bradycardia at lower doses, tachycardia at higher doses.L3
slide 52
Scopolamine
Transderm Scop patch
CautionWash hands thoroughly after placing the patch — touching the eye afterwards causes blurred vision. Effects otherwise similar to atropine.L3
slide 54
SuccinylcholineNamed reactionMalignant hyperthermia with halothane in genetically susceptible people — muscular rigidity, metabolic acidosis, tachycardia and hyperpyrexia. Treat by rapid cooling and dantrolene (Dantrium).L3
slide 70
SuccinylcholineCautionHyperkalemia, and prolonged paralysis (apnea) in patients genetically deficient in plasma cholinesterase or with electrolyte imbalance.L3
slide 70
Atracurium
nondepolarizing blocker
CautionReleases histamine — can produce a fall in blood pressure, flushing and bronchoconstriction.L3
slide 65

Autonomic — adrenergic ANS Pharmacology

Drug or classTierWhat it saysSource
EpinephrineCautionHyperthyroidism — enhanced cardiovascular actions. Cocaine — exaggerated cardiovascular actions because reuptake is prevented. Diabetes — increases release of endogenous glucose stores.L3
slide 87
EpinephrineCautionAdverse effects: anxiety, fear, tension, headache, tremor; cerebral hemorrhage from the rise in blood pressure; cardiac arrhythmias; and pulmonary edema.L3
slide 86
NorepinephrineCautionExtravasation causes blanching and sloughing of skin from extreme vasoconstriction — treated with the alpha antagonist phentolamine.L3
slide 90
DobutamineCautionIncreases atrioventricular conduction — caution in atrial fibrillation. Tolerance may develop with prolonged use.L3
slide 94
Clonidine
Catapres
Named reactionRebound hypertension with abrupt discontinuance. Also lethargy, sedation, constipation and xerostomia.L3
slide 97
Alpha-1 blockers
prazosin, terazosin, doxazosin, tamsulosin, alfuzosin
Named reaction“First-dose” syncope. Also dizziness, lack of energy, nasal congestion, headache, drowsiness and orthostatic hypotension.L3
slide 111
PhenoxybenzamineNamed reactionEpinephrine reversal — it blocks the alpha vasoconstriction of epinephrine but not its beta vasodilation, so blood pressure falls. Block is irreversible; the body must synthesize new receptors, taking at least 24 hours.L3
slide 109
Propranolol
non-selective beta blocker
ContraindicatedCONTRAINDICATED in patients with chronic obstructive pulmonary disease or asthma — beta-2 blockade causes bronchoconstriction. This is the deck's clearest contraindication in Lecture 3.L3
slide 115
Propranolol
non-selective beta blocker
CautionAttenuates the normal physiologic response to hypoglycemia and causes fasting hypoglycemia — the reason for care in diabetics. Decreases glycogenolysis and glucagon secretion; raises LDL cholesterol and triglycerides.L3
slide 115
Propranolol
non-selective beta blocker
Named reactionArrhythmias if stopped abruptly, from up-regulation of beta receptors — never stop a beta blocker suddenly. Also central effects: depression, hallucinations, vivid dreams and nightmares.L3
slide 117
Selective beta-1 antagonists
atenolol, metoprolol, bisoprolol, esmolol
CautionCardioselectivity is LOST at higher doses — which is why “cardioselective” is not a free pass in a patient with airway disease. Useful for hypertension in impaired pulmonary function.L3
slide 120
Labetalol and carvedilolCautionMay cause orthostatic hypotension due to alpha-1 blockade.L3
slide 122
NicotineCautionDepolarizes autonomic ganglia — stimulation first, then paralysis of all ganglia. At higher doses blood pressure falls and gastrointestinal and bladder activity ceases.L3
slide 59