CHARACTERISTICS OF SECOND-LINE DRUGS FOR MTB

Drug
Streptomycin

Bactericidal
Yes

MIC (ug/ml)
0.25 to 2.0

Serum Level
25

Dosing,
Initial dosing
15mg kg per day, 5 to 7 days per wk

After culture conversion
15 to 20 mg/kg for 2 to 3 days per wk

Side Effects
Lichenoid erruptions, renal toxicity, giddiness, perioral numbness, hypersensitivity, vestibular toxicity/ototoxicity, renal toxicity.

Drug
Amikacin

Bactericidal
Yes

MIC (ug/ml)
0.5 to 1.0

Serum Level
25

Dosing
Initial dosing
15mg kg per day for 5 to 7 days per wk
After culture conversion
15 to 20mg/kg for 2-3 days per wk

Remarks
Vestibular screen, baseline audiogram. Monitor creatinine. Adjust dose/interval for renal insufficiency.

Side Effects
Vestibular toxicity, ototoxicity, renal toxicity.

Drug
Capreomycin

Bactericidal
Yes

MIC (ug/ml)
1.25 to 2.5

Serum Level
25

Dosing
Initial Dosing
15mg kg per day for 5 to 7 days per wk

After culture conversion
15 to 20mg/kg for 2-3 days per wk

Remarks
Age greater than 59 10 mg/kg per day

Side Effects
Vestibular toxicity/ototoxicity, hypokalemia,
hypocalcemia, hypomagnesemia, eosinophilia, renal
toxicity.

Drug
Moxifloxacin

Bactericidal
Yes

MIC (ug/ml)
.25 to .5

Serum Level
4 to 6

Dosing
400mg/qd

Remarks
No modification of dose in renal failure.

Side Effects
Class Effect: Al, Mg, Ca antacids, sucralfate and milk
based enteral supplements inhibit absorption. GI upset, dizziness,
hepatitis, hypersensitivity, photosensitivity, headaches,
tendenitis, tendon rupture, insomnia, psychosis, agitation,
depression, paranoia, seizures, thrush, peripheral neuropathy
Good CNS penetration.

Drug
Levofloxacin

Bactericidal
Yes

MIC (ug/ml)
.5 to 1.0

Serum Level
8 to 12

Dosing
500 to 1000 mg/qd (usual 750)

Remarks
Adjust dose for creat cl less than 30.

Side Effects
Class Effect: Al, Mg, Ca antacids, sucralfate and milk
based enteral supplements inhibit absorption. GI upset, dizziness,
hepatitis, hypersensitivity, photosensitivity, headaches,
tendenitis, tendon rupture, insomnia, psychosis, agitation,
depression, paranoia, seizures, thrush, peripheral neuropathy
Good CNS penetration.

Drug
Rifabutin

Bactericidal
Yes

MIC (ug/ml)
greater than 2.0

Serum Level
.3 to .9

Dosing
450mg daily

Remarks
Extensive drug interactions: P-450
induction (less than Rifampin).
Leads to decreased levels of: PI's,
methadone, oral contraceptives,
diabetic meds, fluconazole and
others (see Physicians' Desk Reference
for potential interaction with all
concomitantly administered
prescription drugs). Concentrates in
macrophages.

Side Effects
Decreased white blood count, decreased platelet
count, arthralgia, renal impairment,
hyperpigmentation, uveitis, discoloration of body
fluids, flushing, erythema of head and trunk, GI upset,
hepatitis, nausea.

Drug
Ethionamide

Bactericidal
Weak

MIC (ug/ml)
.3 to 1.2

Serum Level
1 to 5

Dosing
250mg BID or TID OR 250mg am/500 mg/hs or 500 mg daily

Remarks
Increase dose gradually. Monitor
liver function/thyroid function.
Increases effect of cycloserine.

Side Effects
Peripheral neuropathy, nausea, vomiting, abdominal
pain, hypothyroidism, salivation, metallic taste,
hepatitis, giddiness, headache, hypersensitivity,
alopecia, gyneocomastia, hypotension, impotence,
behavior changes, menstrual irregularity,
hypoglycemia, photosensitivity.

Drug
PAS

Bactericidal
No

MIC (ug/ml)
8.0

Serum Level
20 to 60 (6 hr)

Dosing
4gm BID Or 4gr A.M. 2gm hs Or 6gr QD

Remarks
Diarrhea improves with time;
increase dose gradually, mix with
acidic juice or applesauce, avoid
Benadryl. Monitor thyroid function.

Side Effects
GI upset, diarrhea (self limiting), nausea,
hypothyroidisim, lichenoid eruptions, hypokalemia,
hepatitis, thrombocytopenia, increased acidosis in
patient with renal failure.

Drug
Clofazamine

Bactericidal
Weak

MIC (ug/ml)
.12

Serum Level
.5 to 2.0

Dosing
300mg daily for 2 months then 100mg daily

Remarks
Skin problems limited by
sunscreen, lubricants helpful

Side Effects
Hyperpigmentation, GI complaints, acne flare,
retinopathy, ichthyosis, sunburn.

Drug
Cycloserine

Bactericidal
No

MIC (ug/ml)
Not applicable

Serum Level
20 to 35

Dosing
250mg BID or 250mg AM/500 mg/hs

Remarks
Avoid in patients with
seizures/psychotic disease or
ETOH abuse; check level before
increasing dose greater than 500 QD.
Administer with pyridoxine 100
mg QD.

Side Effects
Lichenoid eruption, agitation, psychosis, depression,
seizures, dizziness, headache, slurred speech,
insomnia, Steven's Johnson Syndrome. Adjust dose
in renal insufficiency.

Drug
Linezolid

Bactericidal
Unknown

MIC (ug/ml)
.25 to .5

Serum Level
12 to 24

Dosing
600mg daily

Remarks
Pyridoxine 100 mg daily.

Side Effects
Peripheral neuropathy, optic neuritis (reversible),
anemia, thrombocytopenia, neutropenia, headache,
GI upset, rash, serotonin syndrome, lactic acidosis.

Produced by Heartland National TB Center.
Consultation to healthcare providers at 1-800-TEX-LUNG, www.HeartlandNTBC.org
This product produced with funds awarded by the Centers for Disease Control & Prevention (CDC).