Anti-Mycobacterial Agents (week 10) Flashcards
What are the four Antimycobacterial Agents?
Isoniazid (INH)
Rifampin (RIF)
Pyrazinamide (PZA)
Ethambutol (EMB)
Reaction of TB after immunosuppression, HIV infection, or smoking
Secondary TB
Positive Skin Test Negative Chest Xray Does not feel sick Not infectious Requires treatment to prevent
Latent TB
Positive skin test Abnormal chest Xray Positive sputum Feels sick Contagious Requires treatment for the disease
Active TB
Why does TB treatment happen in multiple waves?
Because slow-growing microbes that show up after the first dose
How many drugs do you start with for Active TB?
Four drugs
Why are multiple drugs used over the course of TB Treatment?
Because of Resistance
What does Multi-drug Resistance mean?
Resistant to both isoniazid and Rifampin
What is Extensively drug-resistant TB?
Resistant to Isoniazid and Rifampin
All fluoroquinolone
First 8 weeks of treatment
Most bacilli killed during this phase
4 drugs used
Intensive Phase of TB Treatment
After first 8 weeks of treatment
Bacilli remaining after intensive phase
At least 2 drugs
Continuation Phase of TB treatment
Surviving TB might cause TB later
Relapse of TB treatment
What is Directly observed therapy (DOT) used for?
Patient non-adherence
What do you assess to see if TB treatment is working?
Bacteriologic evaluation of sputum
Clinical Evaluation
Chest Radiographs
What combination of drugs should not be offered for those who have Latent TB?
Rifampin and Pyrazinamide
What is Isoniazid (INH) used for?
Must use in combination for active TB infection
What is the MOA of Isoniazid (INH)?
Selective for mycobacteria, kills cells wall
How is Isoniazid metabolized?
Acetylation
What are common adverse effects of Isoniazid (INH)?
Peripheral neuropathy
What are some serious side effects of Isoniazid (INH)?
Black Box Warning - Hepatotoxicity
What do you want to know in the PMH before administering Isoniazid (INH)?
Acute liver disease or hx of INH hepatotoxicity
Rate of Acetylation
How is Isoniazid administered?
PO
IM
How do you take Isoniazid?
Empty stomach, either 1 hour before meals or 2 hours after
What is the antidote to Isoniazid (INH)?
Pyridoxine (Vitamin B6)
What is Rifampin used for?
Active TB
Prevention of disease caused by influenza B
What is the MOA of Rifampin?
Inhibits synthesis of RNA and therapy causing defective proteins
What are some common side effects of Rifampin?
Red/Orange discoloration of tears and urine
What are some serious side effects of Rifampin?
Hepatotoxicity
CNS symptoms
What are some drugs that interact with Rifampin?
Protease inhibitors and delavirdine
CYP3A4 inducers
How is Rifampin administered?
Oral
IV
How do you take Rifampin?
Oral - 1 hour before a meal or 2 hours after
IV - slow infusion
What is Pyrazinamide used for and what is the MOA?
TB
Unknown
What are common side effects of Pyrazinamide?
Hyperuricemia
Arthralgia, Myalgia (body aches)
What are serious side effects of Pyrazinamide?
Hepatotoxicity
Articular gout
What do you want to know about PMH before administering Pyrazinamide?
Severe liver disease or acute gout
How is Pyrazinamide administered?
Oral
Once a day, on a empty stomach
What should you take for arthralgia?
NSAID
What is Ethambutol (Myambutol) used for?
Initial treatment of TB
What is the MOA Ethambutol (Myambutol)?
Unknown
What are the common side effects of Ethambutol (Myambutol)?
Hyperuricemia
What are the serious side effects of Ethambutol (Myambutol)?
Optic neuritis
What kind of baseline info should you have before administering Ethambutol (Myambutol)?
Baseline eye test
What should you know in the PMH before administering Ethambutol (Myambutol)?
Optic neuritis
How is Ethambutol administered?
Oral
Take once a day
