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Pharmacology I · Exam 1 · Class of 2028

Killers, Commons and Zebras

Dr. Wood’s own framework for sorting every adverse effect, from the exam review the evening before the paper. 7 killers, 6 groups of commons and 9 zebras, each citing its slide.

Three buckets, from the exam review. The nine badged entries are effects he named himself; the rest are the decks’ adverse effects sorted by his criteria, each citing its slide.
Why a framework beats a list. The side-effects reference on this site is organized by drug, which is the right shape for looking something up and the wrong shape for revising. This one is organized the way he said he thinks about them, which is the shape the question comes in. Use both: the full side-effects chart is here.
How to use thisKillersCommonsZebras

How to use this his framework, not a list

Asked which adverse effects to focus on, Dr. Wood did not give a list — he gave three buckets and told the class to sort everything into them. The sorting is the revision. Take any side effect you have learned and ask: would this kill them, does it happen to nearly everyone on the group, or is it the one strange thing that belongs to this drug alone?

Where he said to aim: “Any time you see those killers or the zebras, those are always things you should look at.” The commons cover a good share of what he asks and mostly come free with the group; the killers and the zebras are each worth about a question.
What is his and what is not. The nine entries badged his example are effects he named himself at the review. The rest are the lecture decks’ own adverse effects sorted by his criteria, each citing its slide. He did not assign those buckets — his rule did, and you can check every one against the slide beside it.

Killers 7

Dangerous. Immediate discontinuation and evaluation. Not necessarily the commonest — these are the ones you warn the patient about in advance, so that they do not decide that skin sloughing off is a normal side effect.
Anaphylaxishis example
Penicillins — the whole class, and the carbapenems and monobactam
The deck asks for monitoring for signs and symptoms of anaphylaxis on the natural penicillins, the penicillinase-resistant penicillins, the antipseudomonal penicillins, aztreonam and the carbapenems — five separate slides. Stop the drug and evaluate.
Antibiotics, Antivirals, and Antifungals · slide 17
Stevens-Johnson syndrome and toxic epidermal necrolysishis example
aminopenicillins; sulfamethoxazole/trimethoprim
His own example of a killer. Skin sloughing is not a side effect to tolerate — he made the point that patients must be told in advance so they do not assume it is normal.
Antibiotics, Antivirals, and Antifungals · slide 21
Suicidal ideation and worsening depressionhis example
isotretinoin
His own example of a killer. The deck instructs monitoring for signs of developing depression, and the drug is also contraindicated in pregnancy and breastfeeding with the iPledge program attached.
Dermatology Medications · slide 27
Clostridioides difficile infection and pseudomembranous colitis
clindamycin; aminopenicillins; fluoroquinolones
Clindamycin is the one classically named for it. Stop the antibiotic and treat.
Antibiotics, Antivirals, and Antifungals · slide 81
Torsades de pointes from QT prolongation
macrolides; fluoroquinolones; azoles
The deck gives QT prolongation its own slide. On the fluoroquinolones it is listed with torsades by name. An arrhythmia, not an inconvenience.
Antibiotics, Antivirals, and Antifungals · slide 58
Serotonin syndrome
linezolid
Listed on the linezolid slide with its triggers: selective serotonin reuptake inhibitors, tyramine-containing foods and pseudoephedrine. Linezolid is a monoamine oxidase inhibitor, which is why an antibiotic is on this list at all.
Antibiotics, Antivirals, and Antifungals · slide 71
Seizures
carbapenems; acyclovir and ganciclovir at high levels
On the carbapenem slide directly. It is the reason the class is not simply the safe broad-spectrum default.
Antibiotics, Antivirals, and Antifungals · slide 44

Commons 6

What actually happens, often. These belong to the GROUP, not the drug. Asked whether the common effects of penicillins, cephalosporins and carbapenems need learning separately, he said “no, they’re all the same” — so they are listed by group here, and the effort goes where a class breaks the pattern.
Every antibiotichis example
Gastrointestinal upset — nausea, vomiting, diarrhea
His own example, and the whole point of the bucket. Almost every antibiotic causes this in somebody. Tell the patient it is expected; it may or may not warrant changing therapy.
Antibiotics, Antivirals, and Antifungals · slide 22
All beta-lactams — penicillins, cephalosporins, carbapenemshis example
Hypersensitivity reaction, rash, diarrhea
Do not learn these three classes' common effects separately. Asked exactly that, he said: “no, they're all the same”. Learn the shared set once and spend the effort where a class breaks the pattern.
Antibiotics, Antivirals, and Antifungals · slide 22
Penicillins
Renal and hepatic monitoring, platelets
Dosing frequency falls with renal impairment.
Antibiotics, Antivirals, and Antifungals · slide 22
Vancomycin
Renal clearance monitoring
Trough levels are checked to confirm efficacy.
Antibiotics, Antivirals, and Antifungals · slide 51
Aminoglycosides
Ototoxicity and nephrotoxicity
Common enough in this class to be the reason troughs are checked at all — the target is an undetectable trough, because it is accumulation that harms.
Antibiotics, Antivirals, and Antifungals · slide 68
Topical retinoids
Retinoid dermatitis — erythema, pruritus, scaling
Expected with the class rather than a reason to stop.
Dermatology Medications · slide 24

Zebras 9

Uncommon, but unique to one drug. “Whenever you hear hoofs beating, normally you should be thinking horses. Sometimes it’s a zebra.” Each is worth about one question — and together with the killers they are where he told the class to look.
Disulfiram-like reaction with alcoholhis example
metronidazole
His own example of a zebra. Uncommon in practice — a patient taking it for an infection is often not drinking — but unique to this drug, and it costs nothing to warn them.
Antibiotics, Antivirals, and Antifungals · slide 86
Red Man syndromehis example
vancomycin
His own example. An infusion-related reaction, not an allergy, which is why the answer is to slow the infusion rather than to stop the drug. He specified two hours.
Antibiotics, Antivirals, and Antifungals · slide 51
Tooth discoloration and depression of skeletal growthhis example
tetracyclines
He pointed at the tetracyclines by name as where a class breaks the common pattern. Doxycycline discolors more than the others; avoid under 8 years old and in the second and third trimesters.
Antibiotics, Antivirals, and Antifungals · slide 63
Chelation with calcium and ironhis example
tetracyclines; fluoroquinolones
The interaction he illustrated with a patient on a prenatal vitamin whose calcium and iron bind up the doxycycline. Both classes complex with cations.
Antibiotics, Antivirals, and Antifungals · slide 63
Achilles tendonitis and tendon rupture
fluoroquinolones
Unique to this class, and paired on the slide with a caution in the under-18s and with peripheral neuropathy.
Antibiotics, Antivirals, and Antifungals · slide 79
Photosensitivity
tetracyclines; fluoroquinolones; topical retinoids
Not dangerous, but it is the one that actually changes what you tell the patient — sunscreen and covering up, because they will be outdoors regardless.
Antibiotics, Antivirals, and Antifungals · slide 63
Teratogenicity
azoles; isotretinoin; tetracyclines
The azole slides carry it three times over. Isotretinoin is contraindicated in pregnancy and breastfeeding outright.
Antibiotics, Antivirals, and Antifungals · slide 104
Bone marrow suppression
flucytosine; ganciclovir
Confined to these agents rather than shared across the antifungals or antivirals.
Antibiotics, Antivirals, and Antifungals · slide 101
Raised serum lipids
isotretinoin
Sits alongside photophobia, arthralgia, headaches, alopecia and brittle nails on the same slide — the price of the most effective acne drug.
Dermatology Medications · slide 27