33 Treatment of Tuberculosis Cupo Flashcards
What are the First-Line Antituberculosis Drugs used?
RIPE: Rifampin (RIF), Isoniazid (INH), Pyrizinamide (PZA), Ethambutol (EMB). Also Rifabutin, Rifapentin
What are the Second Line Antituberculosis Drugs used?
Streptomycin (SM), Cycloserine, p-Aminoslicylic acid, Ethionamide, Amikacin or Kanamycin, Capreomycin, Levofloxacin, Moxifloxacin, Gatifloxacin, Linezolid
How does Rifampin work?
Inhibits RNA synthesis
How does Isoniazid work?
Inhibits cell wall synthesis
How does Pyrazinamide work?
Exact target unclear. Disrupts plasma membrane. Disrupts energy metabolism
How does Ethambutol work?
Inhibits cell wall synthesis
What is the role of the new drug: Rifabutin (Mycobutin)?
Recommended when unacceptable drug interactions with Rifampin. Has a lower potential for CYP450 induction
What is the role of the new drug: Rifapentin (Priftin)?
Recommended for once-weekly continuation phase for HIV (-) adults w/ drug susceptible non-cavitary TB and (-) AFB smears at completion of initial phase smear
What is the general treatment regimen for TB like?
Always consider starting with 4 drug regimens (preferred: RIPE). Initial phase: 2 months. Continuation phase: 4 months (7 months for some patients)
What patients is the 7 month continuation therapy recommended?
1) Patients w/ cavitary pulmonary TB caused by drug susceptibility organisms and whose sputum culture obtained at the time of completion of initial phase is (+). 2) Patients whose initial phase did not include PZA. 3) Patients being treated w/ once weekly INH and rifapentine and whose sputum culture obtained at the time of completion of initial phase is (+)
What is the treatment of Culture-Positive TB (DAILY option)?
Initial Phase: 2 months RIPE daily (total of 56 doses within 8 weeks). Continuation phase: 1) 4 months: INH and RIF daily. 2) 4 months: INH and RIF twice/week. 3) 7 months: INH and RIF daily. 5) 7 months: INH and RIF twice/week
What is the treatment for Culture-Positive TB (Twice-weekly option)?
Initial Phase: 0.5 months: RIPE daily (total 10-14 doses w/in 2 weeks), 1.5 months: RIPE twice/week (12 doses w/in 6 weeks). Continuation Phase: 1) 4 months: INH and RIF twice/week (18 weeks), 2) 7 months: INH and RIF daily (twice/week for 31 weeks)
What is the treatment for Culture-Positive TB (Thrice-weekly option)?
Initial phase: 2 months (RIPE 3 times/week (8 weeks)). Continuation phase: 1) 4 months: INH and RIF 3x/week (18 weeks), 2) 7 months: INH and RIF 3x/week (31 weeks)
What are the recommended uses for the second-line drugs in TB?
When there is a drug intolerance, special population, drug resistance
What is the dosing of Isoniazid (INH) like for QD, 1x/week, 2x/week, 3x/week?
QD (5mg/kg: 300mg). 1-3x/week (15mg/kg: 900mg)
What is the dosing of Rifampin (RIF) like for QD, 1x/week, 2x/week, 3x/week?
Same for all of them: 10mg/kg (600mg)
How is Pyrazinamide (PZA) dosed?
20-25mg/kg/day. Weight: 40-55 (QD: 1,000mg, 2x weekly: 1,500mg, 3x weekly: 2,000mg). Other weight categores are 56-75 and 76-90
How is Ethambutol (EMB) dosed?
15-20mg/kg/day. Weight 40-55kg (QD: 800mg, 2x weekly: 1,200mg, 3x weekly: 2,000mg)
What are the formulations that Isoniazid come in?
Tablets (50, 100, 300mg). Elixer (50mg/5ml). Aqueous solution (100mg/ml) for IV or IM
What are the formulations that Rifampin come in?
Capsule (150, 300mg). Powder for oral administration. Aqueous solution for injection
What are the formulations that Pyrazinamide come in?
Tablet (500mg, scored)
What are the formulations that Ethambutol come in?
Tablet (100, 400mg)
Which first line agents have high CSF concentrations?
INH (90-100%). PZA (~80%)
Which first line agent is primarily renally cleared?
EMB. All others mainly hepatic
Which first line agent doesn’t need renal adjustment?
INH. RIF
Which first line agent doesn’t need hepatic adjustment?
EMB