Antibiotics Quick Guide — Classes, Mechanisms & Prescribing Tips

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Antibiotics Quick Guide — Classes, Mechanisms & Prescribing Tips (Free PDF)

One-page antibiotic cheat sheet for rapid recall — class, mechanism, typical examples, key side effects and prescribing tips.

Immediate takeaway

Carry this one-page PDF during ward rounds and last-minute revision — know the class, one or two examples, and the key ADR to watch.

Download Antibiotics Cheat Sheet (PDF) Preview sample notes

Quick summary table (read in 60 seconds)

ClassExamplesMechanismKey ADRs/Notes
β-lactams (Penicillins)Amoxicillin, AmpicillinCell wall synthesis inhibitors (PBPs)Allergy; GI upset
CephalosporinsCefalexin, CeftriaxoneCell wall synthesisSmall penicillin cross-reactivity; biliary sludging (ceftriaxone)
CarbapenemsImipenem, MeropenemBroad β-lactamsReserved; seizure risk (imipenem)
GlycopeptidesVancomycinPeptidoglycan synthesis inhibitorNephrotoxicity, red-man syndrome
AminoglycosidesGentamicin30S inhibitor (bactericidal)Nephrotoxicity, ototoxicity — monitor levels
MacrolidesAzithro, Clarithro50S inhibitorGI, QT prolongation, CYP interactions
FluoroquinolonesCiprofloxacinDNA gyrase inhibitorTendon risk, QT
Sulfonamides/TMPCo-trimoxazoleFolate synthesis inhibitorsSJS risk, hyperkalaemia
NitroimidazolesMetronidazoleRadicals in anaerobesDisulfiram-like reaction
OxazolidinonesLinezolid50S initiation inhibitorThrombocytopenia; MAOI interactions

Prescribing tips (ward-friendly)

  1. Always check local antibiogram & guidelines before empiric therapy.
  2. Start empiric therapy for suspected sepsis after taking blood cultures — do not delay antibiotics.
  3. Adjust dosing in renal/hepatic impairment; monitor trough levels where indicated (vancomycin, aminoglycosides).
  4. Remember major drug interactions (macrolides, linezolid MAOI effect, CYP interactions).

Short FAQ

Can I use this PDF in clinical practice?This is a quick reference for students. Always check local formularies and dosing protocols before prescribing.

Resources: Free samples | All-21 notes bundle