RIPE
First-Line Anti-Tuberculosis Drugs
Four drugs, four signature side effects — red tears, numb feet, gout, vision loss.
For the FNP boards, active TB treatment is RIPE for two months followed by RI for four more — and each drug carries a signature side effect that boards tests directly. Rifampin turns body fluids orange-red and induces CYP enzymes (warfarin, OCP failures). Isoniazid causes peripheral neuropathy (give B6) and hepatotoxicity. Pyrazinamide causes hyperuricemia and gout flares. Ethambutol causes optic neuritis and red-green color blindness; check vision at baseline. AANP exam vignettes pair a side effect to a drug and ask which to discontinue or which test to monitor. Pyridoxine for INH and baseline ophthalmologic exam for ethambutol are recurring right answers.
- RRifampinTurns body fluids red/orange (tears, urine, sweat — harmless but warn the patient). Hepatotoxic. Potent CYP450 INDUCER — reduces OCP efficacy; add a backup method.
- IIsoniazid (INH)Peripheral neuropathy — give pyridoxine (vitamin B6) to prevent. Hepatotoxic. Can cause drug-induced lupus.
- PPyrazinamideHyperuricemia → gout flares. Hepatotoxic. Avoid in acute gout and severe liver disease.
- EEthambutolOptic neuritis — red-green color blindness and decreased visual acuity. Baseline and monthly eye exams; stop if vision changes.
Clinical Context
Standard active TB regimen: 2 months of all four drugs (intensive phase) followed by 4 months of rifampin + isoniazid (continuation phase) — 6 months total. All four are hepatotoxic; get baseline LFTs and monitor periodically.
Latent TB is treated differently: 9 months of INH alone, or 12 weeks of weekly INH + rifapentine (3HP regimen), or 4 months of daily rifampin. Multi-drug-resistant TB (MDR-TB) requires second-line agents and longer courses.
Key AANP pearls: give pyridoxine (B6) with INH to prevent peripheral neuropathy; warn patients about orange tears/urine from rifampin so they don't panic; monthly color vision testing on ethambutol; counsel contraceptive users that rifampin weakens OCPs.
Related Mnemonics
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- STOP-BANG — Obstructive Sleep Apnea Screen
Sources
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