Step 1 References & Mnemonics
Antiarrhythmics Mnemonics
Class I (Na+ Channel Blockers): "Double Quarter Pounder, Lettuce Mayo, Fries Please"
- IA: Disopyramide, Quinidine, Procainamide
- IB: Lidocaine, Mexiletine
- IC: Flecainide, Propafenone
| Class |
AP Duration Effect |
Toxicity / Notes |
| IA |
Prolongs (Blocks K+ too) |
Quinidine (Cinchonism), Procainamide (Drug-induced lupus) |
| IB |
Shortens |
CNS toxicity. Best for post-MI (ischemic tissue). |
| IC |
No change |
Proarrhythmic in structural heart disease (CAST trial). |
Class III (K+ Channel Blockers)
Mnemonic: "AIDS" - Amiodarone, Ibutilide, Dofetilide, Sotalol
| Drug |
High-Yield Toxins/Facts |
| Amiodarone |
Pulmonary fibrosis, hepatotoxicity, hypo/hyperthyroidism, blue-gray skin. Check PFTs, LFTs, TFTs. Contains iodine. |
| Sotalol |
Beta-blocker with Class III properties. Watch for Torsades de Pointes. |
Diuretics Sites of Action
| Class |
Target / Location |
Key Adverse Effects |
| Loop (Furosemide) |
Na-K-2Cl / Thick Ascending Limb |
Ototoxicity, Hypocalcemia (Loops Lose Ca2+), Sulfa allergy (use Ethacrynic acid instead) |
| Thiazides (HCTZ) |
Na-Cl / Distal Convoluted Tubule |
HyperGLUC (Glycemia, Lipids, Uric Acid, Calcium) |
| K-Sparing (Spironolactone) |
Aldosterone Rec / Collecting Duct |
Hyperkalemia, Gynecomastia (anti-androgen) |
Lipid-Lowering Agents
| Drug Class |
Mechanism |
Toxicity |
| Statins |
Inhibit HMG-CoA Reductase |
Myopathy, Hepatotoxicity (check LFTs) |
| Fibrates |
Activate PPAR-alpha (Upregulate LPL) |
Myopathy (especially if combined with statins) |
| Niacin |
Inhibits lipolysis in adipose tissue |
Flushing (prostaglandin mediated, give NSAIDs) |