Chapter 41 anti tubercular drugs

"The patient is to receive isoniazid (INH) 0.3 g daily. The medication is available as 100-mg tablets. How many tablets will the nurse administer per dose?"

3 tablets

The order for isoniazid (INH) reads: "Give 5 mg/kg PO daily." The patient weighs 275 pounds. What is the amount per dose? Is this a safe dose?

625 mg/dose; no, maximum dose is 300 mg

The nurse anticipates an order for vitamin supplementation for a patient who is receiving INH therapy. What vitamin supplement is usually used with INH? A Folate B Vitamin B6 C Vitamin E D Calcium

B Pyridoxine (vitamin B6) is typically ordered to assist in prevention of the neurologic side effects of the INH.

"A patient will be receiving long-term isoniazid (INH) therapy. What laboratory tests are most impor- tant for the nurse to monitor during therapy? a. Liver enzyme levels b. Hematocrit and hemoglobin level c. Creatinine level d. Platelet count"

a

"The nurse is explaining antitubercular therapy to a patient. The patient asks, "Why do I have to take so many different medications?" What is the nurse's best response? a. "It helps to prevent the tuberculosis from be- coming resistant to the drugs." b. "It makes sure that the disease is cured." c. "These medications will reduce symptoms immediately." d. "You will have fewer side effects.""

a

The nurse is monitoring for liver toxicity in a patient who has been receiving long-term isoniazid therapy. Manifestations of liver toxicity include: (Select all that apply.) a Orange discoloration of sweat and tears b Darkened urine c Dizziness d Fatigue e Visual disturbances f Jaundice

b,d,f

"A patient newly diagnosed with tuberculosis asks the nurse how long he will need to take "all this medi- cine." The nurse replies that drug therapy for active tuberculosis may need to last how long? a. 6 months b. 12 months c. 24 months d. A lifetime"

c

The nurse is teaching a patient who is starting antitubercular therapy with rifampin. Which adverse effects would the nurse expect to see? a Headache and neck pain b Gynecomastia c Reddish brown urine d Numbness or tingling of extremities

c

While monitoring a patient, the nurse knows that a therapeutic response to antitubercular drugs would be: a The patient states that he or she is feeling much better. b The patient's laboratory test results show a lower white blood cell count. c The patient reports a decrease in cough and night sweats. d There is a decrease in symptoms, along with improved chest radiograph and sputum culture results.

d

A patient with tuberculosis has been taking antitubercular drugs. A sputum culture is ordered to test for acid-fast bacilli. When is the best time for the nurse to obtain the sputum culture? A. In the morning B. Noon C. Five o'clock in the evening D. Ten o'clock in the evening

Correct answer: A Rationale: If the prescriber has ordered collection of a sputum specimen to test for acid-fast bacilli, it is best to obtain the sample early in the morning. The most common order is for three consecutive morning specimens, with a repeat specimen several weeks later.

"The patient has new orders for pyrazinamide, 30 mg/ kg/day. The patient weighs 132 pounds. How many milligrams will the patient receive per day? Is this dosage safe? "

1800mg yes max dose is 2 grams (2000mg)

When assessing for adverse reactions to Rifamate (combination isoniazid and rifampin), the nurse would monitor which laboratory values? (Select all that apply.) A Liver function tests B CBC C Sputum cultures D Uric acid levels E Cholesterol

A,B Rifamate can lead to impairment of liver function as well as hematologic disorders. Assessment of sputum cultures confirms the diagnosis but is not related to adverse effects. The drug does not affect uric acid levels or cholesterol.

"The nurse is reviewing the medication list of a pa- tient who has been newly diagnosed with tubercu- losis and will be taking rifampin (Rifadin). Which class of drugs, if taken with the rifampin, may cause increased metabolism? (Select all that apply.) a. Beta blockers b. Proton pump inhibitors c. Selective serotonin reuptake inhibitors d. Oral anticoagulants e. Oral antidiabetic drugs

a d e

Patients who are in the initial period of treatment for tuberculosis need to be taught to perform which pro- cedures? (Select all that apply.) a. Wash their hands and cover their mouths when coughing or sneezing to reduce the spread of tuberculosis. b. Throw away dirty tissues in the proper receptacle. c. Be sure to get adequate rest, nutrition, and relaxation. d. Skip medication doses occasionally if gastric distress occurs. e. Avoid all visitor"

a b c

"The nurse should include which information in the teaching plan for a patient who is taking isoniazid (INH)? a. Urine and saliva may be reddish-orange. b. Pyridoxine (vitamin B6) may be needed to pre- vent neurotoxicity. c. Injection sites should be rotated daily. d. The medication should be taken with an antacid to reduce gastric distress."

b

What information must be provided to a patient receiving rifampin? A. A nonharmful side effect of the drug is red-orange discoloration of urine, sweat, and tears. B.Oral contraception is the preferred method of birth control when using rifampin. C.Peripheral neuropathy is an expected side effect, and the patient should report any numbness or tingling of the extremities. D. The patient will only need to take this medication for the prescribed 14-day period.

A Red-orange discoloration of body fluids is a common side effect of rifampin, but it is not harmful. Rifampin does not cause peripheral neuropathies (INH does), but it does interfere with the effectiveness of oral contraceptives. All antitubercular drugs need to be taken long term in order to eradicate the slow-growing mycobacterium lying deep within the tissues.

Which statement by the patient leads the nurse to believe that the patient has understood the teaching regarding ethambutol (Myambutol)? A. "Dizziness, drowsiness, and decreased urinary output are common with this drug, but they will subside over time." B "Constipation will be a problem, so I will increase the fiber in my diet." C "I will need to have my eyes checked periodically while I am taking this drug." D "This medication may cause my bodily secretions to turn red-orange."

C Ethambutol can cause optic neuritis. Ophthalmologic examinations should be performed periodically to assess visual acuity.

The nurse will teach patients taking rifampin and INH prophylactically secondary to tuberculosis exposure that: A. these drugs will only need to be taken for 7 to 10 days. B. INH may decrease serum glucose in susceptible people. C.oral contraceptives become ineffective when given with rifampin. D. tanning beds may be used to counteract the pale skin tone caused by these medications.

C Women taking oral contraceptives who are prescribed rifampin must be switched to another form of birth control because oral contraceptives become ineffective when given with rifampin. These medications must be taken long term because mycobacterium is slow growing. They can cause photosensitivity, necessitating the use of sunscreen, not tanning beds. Finally, INH may increase, not decrease, serum glucose levels.

When reviewing a patient's medication regimen before discharge, the patient asks why he is taking pyridoxine when he is already taking isoniazid (INH) to treat tuberculosis. What is the nurse's best response? A "Pyridoxine is another antitubercular drug that will work synergistically with the isoniazid." B "You really should not be on that drug. I will check with the doctor." C"Pyridoxine will help prevent numbness and tingling that can occur secondary to the isoniazid." D "Multidrug therapy is necessary to prevent the occurrence of resistant bacteria."

C INH can cause neurotoxicity. Pyridoxine, vitamin B6, is the drug of choice to prevent this adverse reaction. It is not an antiinfective drug and thus will not work to destroy the mycobacterium or prevent drug resistance.

A patient with a diagnosis of tuberculosis (TB) will be taking isoniazid (INH) as part of the anti-TB therapy. When reviewing the patient's chart, the nurse finds documentation that the patient is a "slow acetylator." This means that: A.the dosage of INH may need to be lower to prevent INH accumulation. B.the dosage of INH may need to be higher due to the slow acetylation process. C.he should not take INH. D.he will need to take a combination of anti-TB drugs for successful therapy

Correct answer: A Rationale: When INH is taken by slow acetylators, the INH accumulates because there are not enough liver enzymes to break down the INH. Therefore, the dosages of INH may need to be adjusted downward to prevent toxicity.

The patient's wife is taking rifampin to prevent her from developing a tuberculosis infection. Which statement by the wife indicates that further teaching is needed? A. "Because my oral contraceptives will not work while I am taking rifampin, I will use another form of birth control." B. "I will take the medication for one week and then stop." C. "I will avoid prolonged exposure to the sun." D. "My urine may turn a reddish color when taking rifampin."

Correct answer: B Rationale: Antitubercular therapy is taken for long periods of time, often 24 months. Although this patient does not have an active infection at this time and is taking the rifampin to prevent an infection, the nurse should further investigate the length of time the medication is ordered. All other statements are true.

A patient has an extremely severe infection with a Mycobacterium that is resistant to all but one antitubercular drug; however, the patient has had an allergic reaction to that drug in the past. What does the nurse anticipate as being ordered for this patient? A. A combination of anti tubercular drugs will be chosen to fight the infection. B. The patient will receive the drug and supportive care to help him tolerate the anti tubercular therapy. C. The patient will remain on isolation precautions until his cough clears. D. There is nothing that can be done with this patient.

Correct answer: B Rationale: It must be recognized that the urgency of treating a potentially fatal infection may have to be balanced against any prevailing contraindications. In extreme cases, patients are sometimes given a drug to which they have some degree of allergy with supportive care that enables them at least to tolerate the medication. Examples of such supportive care are treatment with antipyretics (e.g., acetaminophen), antihistamines (e.g., diphenhydramine), or even corticosteroids (e.g., prednisone, methylprednisolone).

A home care nurse is visiting a patient with a diagnosis of TB. The patient traveled abroad two months ago. He lives with his wife and 5-year-old son. The patient tells the nurse that he is concerned his son will also get TB so he wants to share his pills with his son. What is the best response by the nurse? A. "That is a good idea. Children should not be exposed to TB." B. "You should give your son half of the dose you take." C. "Do not share any of your medications with anyone. Contact your son's health care provider to discuss your concerns." D. "Children have an immune system that makes them immune to TB."

Correct answer: C Rationale: Medications of any kind should never be shared with any other person. In particular, antitubercular drugs are age specific. Assessment of age is also important, because the likelihood of adverse reactions and toxicity is increased in elderly patients due to age-related liver and kidney dysfunction. Additionally, the safety of these drugs in children 13 years of age and younger has not been established.

The patient tells the nurse, "I had a shot after I returned from my trip overseas. I thought that was supposed to stop me from getting a tuberculosis infection." What information regarding tuberculosis- related injections does the nurse identify as being true? A. BCG is used to prevent infection with tuberculosis for women of childbearing age. B. A positive result for a PPD test is indicated by redness at the site of injection. C. PPD is a diagnostic injection given intradermally to detect exposure to the TB organism. D. BCG is a vaccine injection derived from an activated strain of Mycobacterium bovis.

Correct answer: C Rationale: PPD is a diagnostic injection given intradermally in doses of 5 tuberculin units (0.1 mL) to detect exposure to the TB organism. A positive result is indicated by induration (not erythema) at the site of injection and is known as the Mantoux reaction, named for the physician who described it. BCG is used in much of the world to vaccinate young children against tuberculosis. Although it does not prevent infection, evidence indicates that it reduces active tuberculosis by 60% to 80% and is even more effective at preventing more severe cases involving dissemination of infection throughout the body.

Four weeks after beginning antitubercular drug therapy on an outpatient basis, the patient reports that he still experiences night sweats. What does the nurse identify as the main concern at this time? A.He is not taking his medication properly. B.More time is needed to see a therapeutic response. C.His infection may be resistant to the drug therapy ordered. D.He may have contracted a different strain of tuberculosis (TB).

Correct answer: C Rationale: The nurse should not jump to conclusions that the patient is not taking his medication properly. An improvement should start to occur within 2 weeks of starting drug therapy, but this may not occur if the patient's TB is not sensitive to the prescribed drugs. An evaluation of the drug therapy will be needed.

A patient is receiving isoniazid (INH) for the treatment of tuberculosis. Which vitamin does the nurse anticipate administering with the INH to prevent isoniazid-precipitated peripheral neuropathies? A.Vitamin C B.Vitamin B12 C.Vitamin D D.Vitamin B6

Correct answer: D Rationale: Pyridoxine (vitamin B6) may be indicated to prevent isoniazid-precipitated peripheral neuropathies and numbness, tingling, or burning of the extremities.

The nurse is counseling a woman who is beginning antitubercular therapy with rifampin. The patient also takes an oral contraceptive. Which statement by the nurse is most accurate regarding potential drug interactions? a "You will need to switch to another form of birth control while you are taking the rifampin." b "Your birth control pills will remain effective while you are taking the rifampin." c "You will need to take a stronger dose of birth control pills while you are on the rifampin." d "You will need to abstain from sexual intercourse while on the rifampin to avoid pregnancy."

a

During antitubercular therapy with isoniazid, the patient received another prescription for pyridoxine. Which statement by the nurse best explains the rationale for this second medication? a "This vitamin will help to improve your energy levels." b "This vitamin helps to prevent neurologic adverse effects." c "This vitamin works to protect your heart from toxic effects." d "This vitamin helps to reduce gastrointestinal adverse effects."

b

When counseling a patient who has been newly diagnosed with TB, the nurse will make sure that the patient realizes that he or she is contagious a during all phases of the illness. b any time up to 18 months after therapy begins. c during the postictal phase of TB. d during the initial period of the illness and its diagnosis.

d