TB pharm mod 1

Question 1

TB pharm

Answer 1

Isoniazid (INH)
Rifampin
Ethambutol
Pyrazinamide
Streptomycin

Question 2

Isoniazid[inh]

**first line most widely used, PO

Answer 2

MOA: Disrupts cell wall synthesis essential functions of mycobacteria

Black box warning related to increased risk of hepatitis - often given with pyridoxine (vitamin B6)

Side effects: peripheral neuropathy, hepatotoxicity, optic neuritis/visual disturbances, hyperglycemia

interactions

• Avoid antacids - reduce drug absorptions
• with rifampin (another TB med) can increase CNS and hepatotoxicity
• with phenytoin, can increase the effects of phenytoin

Question 3

Rifampin

first line, used with lots mycobacterial infections and other uses

PO/IV

Answer 3

MOA: Inhibits protein synthesis via attacking the hydrocarbon ring structure

Side effects: hepatitis, hematologic disorders, red-brown discoloration of the urine and other body fluids

Decreases effects of beta-blockers, benzos, cyclosporins, anticoagulants, antidiabetics, phenytoin, theophylline
- be careful and tell patients they must make their HCP/pharmacist they are on this med

Question 4

Ethambutol

First-line bacteriostatic

Answer 4

MOA: diffusing into the mycobacteria and suppresses RNA synthesis, which inhibits protein synthesis

Side effects: retrobulbar neuritis, blindness

Given PO
Usually used in combo with INH and rifampin
Not for children less than 13

Question 5

Pyrazinamide [pza]

Not for pregnant people in US

Answer 5

Used in combo with other meds

Unknown MOA– but thought to inhibit lipid and nucleic acid synthesis

Side effects: hepatotoxicity, hyperuricemia
PO

Contraindicated in severe hepatic disease or acute gout

Question 6

Streptomycin

very first TB drug

IM only

Answer 6

MOA: aminoglycoside– interfering with normal protein synthesis causing production of faulty proteins within the bacteria

Side effects: ototoxicity, nephrotoxicity, blood dyscrasias

Careful with people on anticoagulants– can increase bleeding