Term
| What is the primary treatment for a latent TB infection? |
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Definition
- Isoniazid 300mg/day x 9 months (some can do 6 months)
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Term
What is the primary treatment for a latent TB infection in a patient with hepatotoxicity?
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Definition
-Rifamycins
- Includes: Rifampin 600mg/day x 4 months +/- INH (may replace INH with Pyrazinamide 15mg/kg/day x 2 months), or Rifabutin 300mg/day x 4 months +/- INH |
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Term
| What is first line for an active TB infection? |
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Definition
- Acronym RIPE for 1st line
- Stands for Rifamycins (Rifampin, Rifabutin), Isoniazid, Pyrazinamide, Ethambutol
- 2nd Line includes: Cycloserine, Ethionamide, LMG FQ's, P-aminosalicylic acid, Streptomycin, Amikacin/Kanamycin, Capreomycin |
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Term
| In terms of the role of RIPE, what does INH do? |
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Definition
| - Bacteriacidal against rapidly dividing cells |
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Term
In terms of the role of RIPE, what do Rifamycins do?
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Definition
| - Sterilizing activity against rapidly dividing and semi-dormant cells |
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Term
In terms of the role of RIPE, what does pyrazinamide do?
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Definition
| - Greatest effect on dormant/semi-dormant strains contained within macrophages and acidic environments |
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Term
In terms of the role of RIPE, what does ethambutol do?
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Definition
| - Helps prevent rifampin resistance when primary INH resistance present |
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Term
| What is the typical dosage of INH and what does can not be used in HIV+ patients? |
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Definition
- 300mg QD or 900 mg BIW or TID.
- 900 mg BIW not for HIV+ patients with CD4 <100 |
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Term
| What are the adverse effects of INH? |
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Definition
- Hepatotoxicity (increased risk with Rifampin)
- Neurologic Toxicity (B6). Supplement with B6 50-100mg/day |
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Term
| What should one especially avoid when using INH? |
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Definition
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Term
| What should we monitor when someone is on INH? |
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Definition
- LFT's monthly
- Opthalmic exam (optic neuritis)
- TDM of antiepileptic medications (carbamazapine, Phenytoin) |
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Term
| What is the typical dosage of Rifampin, and which is not for HIV+ patients? |
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Definition
- 600 mg/day, BIW, or TIW
- BIW not for HIV+ with CD4 <100
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Term
| What are the adverse effects of Rifampin? |
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Definition
| - Most important are orange secretions and hepatotoxicity |
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Term
| What is significant regarding Rifampin drug interactions |
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Definition
- STRONG INDUCER, not substrate. Therefore, it reduces drug concentrations of other medications
- Saquinavir? |
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Term
| What are the adverse reactions of Rifabutin? |
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Definition
- Orange Secretions
- Hepatotoxicity
- GI intolerance
- Neutropenia
- Dose-related uveitis (450mg/d) |
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Term
| What are the drug interactions involving Rifabutin? |
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Definition
- Less potent inducer of CYP3A4
- Substrate of 3A4
-Increased Rifabutin levels with protease inhibitors
- Increase Rifabutin dose with NVP and EFV (300mg and 450mg, respectively) |
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Term
| What is the dosing, A/E, and monitoring of Pyrazinamide? |
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Definition
- Weight based dosing
- Hepatotoxicity, GI symptoms, Hyperuricemia, acute gouty arthritis, rash
- Monitor uric acid, liver chemistry particularly with rifampin |
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Term
| Is there a special dosing for renal disease in Pyrazinamide? |
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Definition
| - Yes, in renal disease there is an accumulation of metabolites. Therefore, dose reduce to TIW after dialysis |
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Term
| What is the activity of ethambutol, what are the A/E's, and when do you adjust for clearance? |
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Definition
- Bacteriostatic
- Dose related ocular toxicity
- Dose adjust in CrCl < 50ml/min |
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Term
| What is the duration of the initial phase of RIPE therapy? |
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Definition
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Term
| What is the dosing in the continuation phase? |
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Definition
nDosing may be done QD, QW, BIW, TIW
–QW and BIW not for HIV+ patients
–DOT not necessary for QD dosing
n4 months minimum (total 6 months)
n7 months recommended for:
–Cavitation with (+) Cx at 2 months
–No PZA in initial regimen
–Once weekly INH/Rifapentine with (+) cx at 2 months
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Term
| In second line treatments for TB, which ones are off-label usage? |
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Definition
- FQ's (LMG)
- Amikacin/Kanamycin |
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