Antibiotics Quick Guide — Classes, Mechanisms & Prescribing Tips | MedicalNotes.in
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.
Quick summary table (read in 60 seconds)
| Class | Examples | Mechanism | Key ADRs/Notes |
|---|---|---|---|
| β-lactams (Penicillins) | Amoxicillin, Ampicillin | Cell wall synthesis inhibitors (PBPs) | Allergy; GI upset |
| Cephalosporins | Cefalexin, Ceftriaxone | Cell wall synthesis | Small penicillin cross-reactivity; biliary sludging (ceftriaxone) |
| Carbapenems | Imipenem, Meropenem | Broad β-lactams | Reserved; seizure risk (imipenem) |
| Glycopeptides | Vancomycin | Peptidoglycan synthesis inhibitor | Nephrotoxicity, red-man syndrome |
| Aminoglycosides | Gentamicin | 30S inhibitor (bactericidal) | Nephrotoxicity, ototoxicity — monitor levels |
| Macrolides | Azithro, Clarithro | 50S inhibitor | GI, QT prolongation, CYP interactions |
| Fluoroquinolones | Ciprofloxacin | DNA gyrase inhibitor | Tendon risk, QT |
| Sulfonamides/TMP | Co-trimoxazole | Folate synthesis inhibitors | SJS risk, hyperkalaemia |
| Nitroimidazoles | Metronidazole | Radicals in anaerobes | Disulfiram-like reaction |
| Oxazolidinones | Linezolid | 50S initiation inhibitor | Thrombocytopenia; MAOI interactions |
Prescribing tips (ward-friendly)
- Always check local antibiogram & guidelines before empiric therapy.
- Start empiric therapy for suspected sepsis after taking blood cultures — do not delay antibiotics.
- Adjust dosing in renal/hepatic impairment; monitor trough levels where indicated (vancomycin, aminoglycosides).
- 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.