Chapter 41 - Antitubercular Drugs

6 drug interactions with isoniazid

antacids (reduce absorption causing decreased isoniazid), cycloserine, ethionamide, rifampin (additive effects which can cause increased CNS and hepatic tox), phenytoin and carbamazepine (decreased metabolism causing increased effects of these drugs)

3 drug classes used as supportive care when treating TB in those with allergies or contraindications to the medication

antipyretics, antihistamines, corticosteriods

The nurse is treating a pt starting antiTB therapy with rifabutin. What are the possible adverse effects? a. headache and neck pain b. GI tract disturbances c. reddish brown urine. d. numbness or tingling of extremities e. gynecomastia f. neutropenia

b, c, f

nurse is monitoring for liver tox in pt who is on long term isoniazid. Which of these are manifestations of liver tox? a. orange sweat and tears b. darkened urine c. fatigue e. visual disturbances f. jaundice

b, d, f

therapeutic response to antiTB drugs include: a. pt states they are feeling much better b. pts lab test results show a lower WBC count c. pt reports a decrease in cough and night sweats d. decrease in symptoms along with improved chest xray and sputum culture results

d

When is a TB pt contagious?

during the initial period of illness and its diagnosis

isoniazid can cause false positive readings on what urine tests?

glucose

3 adverse effects of rifampin

hepatitis, hematologic disorders, red-orange-brown secretions (urine, feces, saliva, sputum, sweat, tears, etc)

most widely used antitubercular drug as sole drug in prophylaxis, or in combination in treatment of TB

isoniazid

4 drug regiment given to TB pt before susceptibility test results are known

isoniazid, rifampin, pyrazinamide, ethambutol or streptomycin

isoniazid can cause increase in serum levels of what type of tests?

liver function

What adverse effects does pyridoxine help prevent in isoniazid therapy?

neurologic (numbness, tingling)

contraindication of ethambutol

optic neuritis

rifampin may decrease the effects of?

oral contraceptives

2 forms of isoniazid

oral, injectable

2 forms of rifampin

oral, parenteral

5 adverse effects of isoniazid

peripheral neuropathy, hepatotoxicity, optic neuritis, visual disturbances, hyperglycemia

black box warning of isoniazid

potential hepatitis

2 contraindications of isoniazid

previous isoniazid associated hepatic injury, acute liver disease

what supplement is often given with isoniazid?

pyridoxine (vitamin b6)

2 notable adverse reactions of isoniazid

pyridoxine deficiency, liver toxicitity

broad spectrum bactericidal drug that inhibits many mycobacterium species via inhibition of protein synthesis

rifampin

has activity against mycobacterium spp as well as Meningococcus, haemophilus influenzae type b, and M. leprae

rifampin

a derivative of rifampin with a much longer duration of action and possibly better efficacy

rifapentine

very first drug available for treating TB, aminoglycoside antibiotic. Very toxic, but used in multidrug resistant TB infections

streptomycin

an infectious disease caused by species of mycobacterium, usually M. tuberculosis

tuberculosis

isoniazid is broken down in the liver. slow __________ may cause isoniazid to accumulate because they cannot fully break it down.

acetylators

3 relative contraindications of antitubercular drugs

allergy, renal or liver dysfunction

Which patient statement indicates to the nurse that the patient understands the discharge teaching for ethambutol? "Constipation will be a problem, so I will increase the fiber in my diet." "Dizziness and drowsiness are common adverse effects with this drug." "I will need to have my vision checked periodically while I am taking this drug." "This medication may cause my bodily secretions to turn red-orange-brown."

"I will need to have my vision checked periodically while I am taking this drug."

Before discharge, the nurse is reviewing a patient's prescribed medication regimen for tuberculosis (TB). The patient asks the nurse why pyridoxine has been prescribed while continuing to take isoniazid to treat TB. What is the nurse's appropriate response? "Multidrug therapy is necessary to prevent the occurrence of resistant bacteria." "You really should not be on that drug. I will check with the health care provider." "Pyridoxine is another antitubercular drug that will work synergistically with the isoniazid." "Pyridoxine will help prevent numbness, and tingling that can occur secondary to the isoniazid."

"Pyridoxine will help prevent numbness, and tingling that can occur secondary to the isoniazid."

What information would the nurse provide to a patient prescribed rifampin? Oral contraception is the preferred method of birth control when using rifampin. The patient will only need to take this medication for the prescribed 14-day period. A nonharmful adverse effect of this medication is red-orange discoloration of urine, sweat, tears, skin, salvia, and feces. Peripheral neuropathy is an expected side effect, and the patient should report any numbness or tingling of the extremities.

A nonharmful adverse effect of this medication is red-orange discoloration of urine, sweat, tears, skin, salvia, and feces.

When assessing for adverse effects to Rifamate (combination isoniazid and rifampin), the nurse would monitor which laboratory values? (Select all that apply.) Cholesterol Uric acid levels Sputum cultures Liver function tests Complete blood cell count

Liver function tests Complete blood cell count

Which instruction would the nurse include for a patient prescribed rifampin and isoniazid prophylactically secondary to TB exposure? Advise that these drugs will only need to be taken for 7 to 10 days. Remind that sunscreen is not needed during outdoor activities. Explain that isoniazid may decrease blood serum glucose in susceptible people. Emphasize that oral contraceptives become ineffective when given with rifampin.

Emphasize that oral contraceptives become ineffective when given with rifampin.

The nurse anticipates a prescription for vitamin supplementation for a patient who is receiving isoniazid therapy. What vitamin supplement is usually prescribed with isoniazid? Folate Calcium Vitamin E Vitamin B6

Vitamin B6