1st Line Medications

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Treatment regimens that include four different first-line antituberculosis medications are recommended for the initial treatment of TB in adults. The initial regimen should include INH, RIF, PZA, and EMB unless there are contraindications to any of the drugs or if the patient is pregnant.a Rifampin should generally not be used in patients who are receiving HIV medications.

All antituberculosis medications should be given concurrently, as a single dose, in order to prevent development of resistant organisms and to enhance adherence, as well as achieve optimum drug serum levels. This card is not intended as a complete reference for treatment of tuberculosis. 

Drug

Isoniazid (INH) 

 

 

 

DOSAGES  GIVEN  IN  MG/KG;  [MAXIMUM  DOSE]
Doses in mg/kg based on lean body weight
Maximum does regardless of weight

Daily
5 [300 mg]

Once Weekly
15 [900 mg]
All intermittent regimens must be directly observed

2x Weekly
15 [900 mg]
All intermittent regimens must be directly observed

3x Weekly
15 [900 mg]
All intermittent regimens must be directly observed

Adverse Reactions
Hepatic enzyme elevation, hepatitis, rash, peripheral neuropathy,  mild CNS effects, drug interactions

Monitoring
In patients with pre-existing liver disease or who develop abnormal liver function that does not require discontinuation of the drug; LFTs should be done  monthly  & when symptoms  occur.

Comments
Hepatitis risk increases with age,  alcohol use, & concurrent use of other hepatotoxic drugs. Supplementation with pyridoxine  in patients with nutritional  deficiency, medical conditions associated with peripheral neuropathy (i.e., diabetes, chronic renal failure/dialysis, HIV) and during pregnancy is recommended.

Rifampin (RIF) 

 

 

 

 

 

DOSAGES  GIVEN  IN  MG/KG;  [MAXIMUM  DOSE]
Doses in mg/kg based on lean body weight
Maximum does regardless of weight

Daily
10 [600 mg]

Once Weekly
N/A

2x Weekly
10 [600 mg]
All intermittent regimens must be directly observed

3x Weekly
10 [600 mg]
All intermittent regimens must be directly observed

Adverse Reactions
GI intolerance, drug interactions, hepatitis, bleeding problems, flu-like symptoms, orange  discoloration of bodily fluids

Monitoring
Drug interactions should be noted.

Comments
Significant interactions with certain HIV medications, methadone, oral contraceptives, & other  drugs.f    Educate patients about normal discoloration of bodily fluids.

Fixed-dose combinations of INH+RIF+PZA (Rifater®) and INH + RIF (Rifamate®) are preferred when DOT is not used.

Rifapentine (RPT) 

 

 

 

 

 

DOSAGES  GIVEN  IN  MG/KG;  [MAXIMUM  DOSE]
Doses in mg/kg based on lean body weight
Maximum does regardless of weight

Daily
N/A

Once Weekly
10-15 [600-900 mg] (continuation phase)
All intermittent regimens must be directly observed

2x Weekly
N/A

3x Weekly
N/A

Adverse Reactions
Hematologic  toxicity, GI symptoms,   polyarthralgia, hepatotoxicity, pseudojaundice, flu-like symptoms, orange  discoloration of bodily fluids

Monitoring
Although drug interactions are less problematic than with RIF, they still require monitoring.
See Morbidity & Mortality Weekly Report 52(RR-11), p.47

Comments
Used once weekly with INH, in the continuation phase only for HIV-seronegative patients with non-cavitary, drug-susceptible pulmonary TB who have negative sputum smears at 2 months.
See Morbidity & Mortality Weekly Report 52(RR-11), p.47

Rifabutin (RBT) 

 

 

 

 

 

DOSAGES  GIVEN  IN  MG/KG;  [MAXIMUM  DOSE]
Doses in mg/kg based on lean body weight
Maximum does regardless of weight

Daily
5 [300 mg]

Once Weekly
N/A

2x Weekly
5 [300 mg]
All intermittent regimens must be directly observed

3x Weekly
5 [300 mg]
All intermittent regimens must be directly observed

Adverse Reactions
Cutaneous reactions, GI reactions, flu-like symptoms, hepatotoxity, severe immunologic reactions, orange discoloration of bodily fluids, drug interactions due to induction of hepatic microsomal enzymes, uveitis

Monitoring
Although drug interactions are less problematic than with RIF, they still require monitoring.

Comments
Used as a substitute   for RIF if patient demonstrates RIF intolerance or is taking drugs that have unacceptable interactions with RIF.

Not yet approved by the U.S. Food and Drug Administration for use in the treatment of tuberculosis.

Pyrazinamide (PZA) 

 

 

 

 

Patient's Weight   Daily  2x weekly  3x weekly 
40-55 kg 18.2-25.0 [1g] 36.4-50.0 [2 g] 27.3-37.5 [1.5  g]
56-75 kg 20.0-26.8 [1.5  g] 40.0-53.6 [3 g] 33.3-44.6 [2.5  g]
76-90 kg 22.2-26.3 [2 g] 44.4-52.6 [4 g] 33.3-39.5 [3 g]

Adverse Reactions
Hepatitis,  GI intolerance, rash, joint aches, hyperuricemia, gout (rare)

Monitoring
LFTs in  patients with underling liver disease or in conjunction  with RIF for treatment  of LTBI; baseline  uric acid.

Comments
Little information about safety of use in pregnancy. Reduce dose in patients with renal insufficiency.

Ethambutol (EMB)

 

 

 

 

Patient's Weight   Daily  2x weekly  3x weekly 
40-55 kg 14.5-20.0 [.8 g] 36.4-50.0 [2 g] 21.8-30.0 [1.2  g]
56-75 kg 16.0-21.4 [1.2  g] 37.3-50.0 [2.8  g] 26.7-35.7 [2 g]
76-90 kg 17.8-21.1 [1.6  g] 44.4-52.6 [4 g] 26.7-31.6 [2.4  g]

Adverse Reactions
Optic neuritis

Monitoring
Baseline visual acuity tests, color discrimination tests, and questioning each month.

Comments
Adjust dose or dosing internal when creatinine clearance is <30  ml/minute.