Anti Tubercular Agents

7/28/2019 Anti Tubercular Agents

1/22

Tuberculosis (TB)

Caused by an acid

fast-fast bacillus

Mycobacterium

tuberculosis

(tubercle bacillus)


2/22

Mycobacterium Infections

Common Infection Sites

lung (primary site)

brain bone

liver


3/22

Mycobacterium Infections

Tubercle bacilli are conveyed by

droplets.

Droplets are expelled by coughing or

sneezing, then gain entry into the body

by inhalation.

Tubercle bacilli then spread to other

body organs via blood and lymphatic

systems.

Tubercle bacilli may become dormant,

or walled off by calcified or fibrous

tissue.


4/22

Anti tubercular Drugs

Streptomycin- the first drug used

to treat TB

Isoniazid (INH)- discovered in

1952, was the 1storal drug

preparation effective against thetubercle bacillus.

Pyridoxine ( Vit. B6)- usually given

in combination with INH to avoidpossible occurrence ofPeripheral

Neuropathy


5/22

Prophylactic Therapy

Family Members of a TB patient are

usually given prophylactic doses of

INH for 6 months to 1 year.

Contraindication: Liver Disease

( may cause INH-induced liver

damage)


6/22

Guide Question?

When a person is diagnosed with TB,the family members are usually

given prophylactic dose of what

antitubercular drug?

a. Streptomycin

b. Rifampicin

c. Pyrazinamided. INH


7/22

Drug Combinations

( Duration of treatment is reducedfrom 2 years to 6-9 months)

INH + Rifampin

INH+Rifampin+ EthambutolINH+Rifampin+Pyrazinamide

(Rifampin & Ethambutol noteffective when given alone)


8/22

Multidrug Therapy

EffectiveDivided into 2 phases:

Initial Phase ( 2 months)

Second Phase ( next 4-7 months)Multidrug Resistance persists:

Aminoglycosides (Streptomycin,

kanamycin, amikacin)

Fluoroquinolones (ciprofloxacin,

ofloxacin)


9/22

Anti tubercular Agents

Primary Agents

Secondary Agents isoniazid* capreomycin

ethambutol cycloserine

pyrazinamide (PZA) ethionamide rifampin kanamycin

streptomycin para-aminosalicyclic

acid(PSA)

*most frequently used


10/22

First-Line Drugs- are considered

more effective & less toxic than

second-line drugs.

Second-line Drugs- maybe used in

combination with first-line drugs,especially to treat disseminated

TB.


11/22

Mechanism of Action

Protein wall synthesis inhibitors

streptomycin, kanamycin,

capreomycin, rifampin, rifabutin

Cell wall synthesis inhibitors

cycloserine, ethionamide,

isoniazid


12/22

Mechanism of Action isoniazid (INH)

Drug of choice for TB

Resistant strains of

mycobacterium emerging

Metabolized in the liver through

acetylationwatch for slow

acetylators


13/22

Side Effects

INH

peripheral neuritis,

hepatotoxicity

ethambutol

retrobulbar neuritis, blindness

rifampin

hepatitis, discoloration of urine,

stools


14/22

Guide Question

A client who is taking rifampin (Rifadin) as part ofthe medication regimen for the treatment of

tuberculosis calls the clinic nurse and reports

that her urine is a red-orange color. The nurse

tells the client to:

a. Come to the clinic to provide a urine sample

b. Stop the medication until further instructions

are given by the physician

c. Take the medication dose with an antacid to

prevent this adverse effect

d. Expect a red-orange color in urine, feces, sweat,

sputum, and tears as a harmless side effect


15/22

Antitubercular Therapy

Effectiveness depends upon

Type of infection

Adequate dosing

Sufficient duration of treatment

Drug compliance

Selection of an effective drugcombination


16/22

Nursing Implications

Obtain a thorough medical history andassessment.

Perform liver function studies in patients

who are to receive isoniazid or

rifampin(especially in elderly patients or those

who use alcohol daily).

Assess for contraindications to thevarious agents, conditions for cautious

use, and potential drug interactions.


17/22

Patient education is CRITICAL:

Therapy may last for up to 24 months.

Take medications exactly as ordered,at the same time every day.

Emphasize the importance of strict

compliance to regimen for

improvement of condition or cure.

Remind patients that they are

contagious during the initial period of

their illnessinstruct in proper

hygiene and prevention of the spread of

infected droplets.


18/22

Emphasize to patients to take care

of themselves, including adequate

nutrition and rest.

Patients should not consume

alcohol while on these medications

nor take other medications,including OTC, unless they check

with their physician.

Diabetic patients taking INHshould monitor their blood glucose

levels because hyperglycemia may

occur.


19/22

INH and rifampin cause oral

contraceptives to become ineffective;

another form of birth control will be

needed.

Patients who are taking rifampin

should be told that their urine, stool,

saliva, sputum, sweat, or tears maybecome reddish-orange; even contact

lenses may be stained.

Vitamin B6 may is needed to combat

peripheral neuritis associated with

INH therapy.


20/22

Guide Questions

A client has been taken isoniazid (INH)for a month and a half. The client

complains to the nurse about

numbness, paresthesias, and tingling in

the extremities. The nurse interpretsthat the client is experiencing.

a. Small blood vessel spasm

b. Impaired peripheral circulationc. Hypercalcemia

d. Peripheral neuritis


21/22

Monitor for side effects

Instruct patients on the sideeffects that should be reported

to the physician immediately.

These include fatigue, nausea,

vomiting, numbness and

tingling of the extremities, fever,

loss of appetite, depression,

jaundice


22/22

Monitor for therapeutic effects

Decrease in symptoms of TB,such as cough

and fever

Lab studies (culture and

sensitivity tests)

and CXR should confirm clinical

findings

Watch for lack of clinical

response to therapy, indicating

possible drug resistance

Anti Tubercular Agents

Documents

Transcript of Anti Tubercular Agents