ch 10
Introduction to Clinical Pharmacology
Chapter 10
Antitubercular Drugs
Learning Objectives
Discuss the drugs used in the treatment of mycobacteria for tuberculosis (TB).
Explain the uses, general drug actions, contraindications, precautions, interactions, and general adverse reactions associated with the administration of the antitubercular drugs.
Distinguish important preadministration and ongoing assessment activities the nurse should perform on the client taking an antitubercular drug.
List nursing diagnoses particular to a client taking an antitubercular drug.
Describe directly observed therapy (DOT).
Examine ways to promote an optimal response to therapy, how to manage adverse reactions, and important points to keep in mind when educating clients about the use of the antitubercular drugs.
Introduction to Tuberculosis
Tuberculosis (TB) is caused by Mycobacterium tuberculosis
Three kinds of infection: latent, active, and extrapulmonary
Leading cause for death in clients with human immunodeficiency virus (HIV)
Prevalent in Asia and sub-Saharan Africa
Significance
Global travel and latent TB
Resistance to drug therapy
Drugs Used to Treat Tuberculosis
Classified into two tiers:
Primary (first line)
Secondary (second line)
TB responds well to long-term treatment with a combination of three or more antitubercular drugs
Antitubercular Drugs—Actions
Bacteriostatic and bactericidal against M. tuberculosis bacillus
Action: inhibits bacterial cell wall synthesis, which slows the multiplication rate of the bacteria
Example of bactericidal
Isoniazid
Examples that have some bactericidal properties
Rifampin
Streptomycin
Antitubercular Drugs—Uses
Used:
to treat infections with M. tuberculosis in either a Standard Treatment Protocol
prophylactically for latent TB infection
Latent TB Treatment
Given to prevent individuals from developing active TB who have a positive skin/blood test for M. tuberculosis but are not infectious
Standard latent TB treatment is 6 to 9 months of isoniazid with a biweekly dosing schedule
Difficulty with adherence
Standard Treatment Protocol for Active TB
Initial phase (~2 months)
Drugs are used to kill rapidly multiplying M. tuberculosis and to prevent drug resistance
Rifampin, isoniazid, pyrazinamide, and ethambutol
Continuing phase (~4 months)
Only rifampin and isoniazid
Multi Drug Resistant TB (MDR-TB)
Can develop due to lack of adherence
Should be considered if a client is not responding to standard treatment
Drugs used to treat MDR-TB
Pretomanid and bedaquiline (interfere with bacterial enzymes)
Must be used in combination with linezolid
Pharmacology in Practice Exercise #1
A nurse is caring for a client with extrapulmonary TB in a long-term care facility. Which of the following organs are frequently affected by extrapulmonary TB? Select all that apply.
Heart
Liver
Spleen
Brain
Kidneys
Ethambutol—Adverse Reactions
Generalized Reactions:
Dermatitis and pruritus
Joint pain
Anorexia
Nausea and vomiting
Serious Adverse Effects:
Anaphylaxis
Optic neuritis
Ethambutol—Contraindications and Precautions
Contraindicated in clients:
with a history of hypersensitivity
younger than 13 years
Used cautiously in clients with:
pregnancy (pregnancy category B)
hepatic or renal impairment
diabetic retinopathy
cataracts
Isoniazid—Adverse Reactions
Generalized Reactions:
Nausea and vomiting
Epigastric distress
Fever
Skin eruptions
Hematologic changes
Jaundice
Hypersensitivity
Toxicity:
Peripheral neuropathy
Severe hepatitis
Isoniazid—Contraindications and Precautions
Contraindicated in clients:
with a history of hypersensitivity
Used cautiously in clients with:
pregnancy (pregnancy category C) or lactation
hepatic or renal impairment
Isoniazid—Interactions
Pyrazinamide—Adverse Reactions
Generalized Reactions:
Nausea and vomiting
Diarrhea
Myalgia
Rashes
Toxicity:
Hepatotoxicity
Pyrazinamide—Contraindications and Precautions
Contraindicated in clients with:
a history of hypersensitivity
acute gout
severe reaction to the drug like jaundice
Used cautiously in clients with:
pregnancy (pregnancy category C) or lactation
hepatic or renal impairment
HIV infection
diabetes mellitus
Pyrazinamide—Interactions
Rifampin—Adverse Reactions
Generalized Reactions:
Nausea and vomiting
Epigastric distress, heartburn
Fatigue
Vertigo
Rash
Reddish-orange discoloration of body fluids
Hematologic changes, renal insufficiency
Rifampin—Contraindications and Precautions
Contraindicated in clients with:
a history of hypersensitivity
Used cautiously in clients with:
pregnancy (pregnancy category C) or lactation
hepatic or renal impairment
Rifampin—Interactions
Pharmacology in Practice Exercise #2
A nurse will be following a client being treated prophylactically with the drug, isoniazid, for latent TB. The treatment lasts for many months and ongoing assessment reveals that the client drinks alcohol frequently. The nurse should monitor specifically for which of the following adverse reactions in this client?
Peripheral neuropathy
Anaphylactoid reactions
Severe hepatitis
Epigastric distress
Nursing Process—Client Receiving an Antitubercular Drug #1
Preadministration Assessment
Objective Data
Positive skin test (Mantoux or purified protein derivative —PPD) (takes 48-72 hours)
Positive QuantiFERON-TB Gold In-Tube blood test
General appearance (weight loss, sweating)
Vital signs (especially fever)
Description of the infections—cough, color of sputum if productive
Lab results, complete blood count, and hepatic/kidney function tests
Nursing Process—Client Receiving an Antitubercular Drug #2
Preadministration Assessment (continued)
Subjective Data
Current symptoms of infection including malaise, fatigue, and loss of appetite
Drug history, particularly if treated before for TB
Social history— association with those who might have had TB
Travel history to areas where the disease is prevalent
Nursing Process—Client Receiving an Antitubercular Drug #3
Ongoing Assessment
If hospitalized, take vital signs every 4 hours or as ordered
If in the community, teach the client and family to monitor daily for adverse reactions
Notify the primary health care provider if there are changes in the vital signs, if signs and symptoms worsen, or if there is the appearance of adverse reactions
Nursing Process—Client Receiving an Antitubercular Drug #4
Nursing Diagnoses
Risk for Injury related to extremity numbness caused by neurotoxicity
Imbalanced Nutrition: Less Than Body Requirements related to gastric upset and general poor health status
Risk for Ineffective Health Management related to indifference, lack of knowledge, long-term treatment regimen, other factors
Nursing Process—Client Receiving an Antitubercular Drug #5
Planning
Expected client outcomes may include:
Optimal response to antitubercular therapy
Management of common adverse drug reactions
Confidence and understanding and adherence to the prescribed medication regimen
Nursing Process—Client Receiving an Antitubercular Drug #6
Implementation
Promoting an optimal response to therapy
Allow time for the client and family members to ask questions
Assess for health literacy and ask the client what they think may be causing the illness (cultural beliefs)
Utilize interpretive services if needed and translated client education tools
Refer the client to other health care workers, such as a social service worker or a dietitian
Nursing Process—Client Receiving an Antitubercular Drug #7
Implementation
Monitoring and Managing Client Needs
Risk for Injury Related to Extremity Numbness Caused by Neurotoxicity
Teach client the reason and importance of taking vitamin B6 if prescribed
Teach client to immediately report any strange sensations that might indicate neurotoxicity such as the sensation of a glove being over the hand, sensory loss, or paralysis
Nursing Process—Client Receiving an Antitubercular Drug #8
Implementation
Monitoring and Managing Client Needs
Imbalanced Nutrition Less Than Body Requirements
Teach the client who uses alcohol to reduce alcohol consumption to reduce the risk of hepatitis
Teach the client to take the vitamin B6 supplement if prescribed
Explain to clients that their bodily fluids may turn a reddish-orange (implications with contacts) and to differentiate between the color of jaundice
Carefully monitor monthly for liver dysfunction (anorexia, nausea, vomiting, fatigue, weakness, yellowing of skin or eyes, darkening of the urine, or numbness in hands and feet)
Nursing Process—Client Receiving an Antitubercular Drug #9
Implementation
Monitoring and Managing Client Needs
Ineffective Health Management
Directly observed therapy (DOT)—client makes periodic visits to the office of the primary care provider and the antitubercular drug is taken in the presence of the nurse
DOT can also take place in the client’s home, place of employment, school with a home care/community health nurse or using video monitoring (Skype, FaceTime, tele-health platforms)
Pharmacology in Practice Exercise #3
A nurse is caring for a client with TB on an outpatient basis who has been prescribed antitubercular drugs. Which of the following is an important teaching point for the nurse to emphasize to prevent the risk of hepatitis in the client with TB?
Take the new multidrug tablets
Use DOT to take drugs on an outpatient basis
Take vitamin B6 according to prescription
Minimize alcohol consumption
Nursing Process—Client Receiving an Antitubercular Drug #10
Implementation—Educating the Client and Family
Develop a teaching plan for the client and family to include:
Integration of client’s cultural beliefs and individual fears about how the bacteria invade the body and how the drugs work to kill it
Information about TB’s causes, communicability, and need for long-term therapy
Drug therapy regimen using visual props or educational materials
Reason for various combinations of drugs used in treatment of TB
Urging the client to take the drugs exactly as directed by the health care provider
Nursing Process—Client Receiving an Antitubercular Drug #11
Implementation—Educating the Client and Family (continued)
Develop a teaching plan for the client and family to include:
Adverse reactions
DOT therapy if indicated
Measures to decrease GI upset
Avoiding alcohol and the use of nonprescription drugs especially those containing aspirin unless directed to do so by their provider
Education on periodic monitoring of laboratory, diagnostic tests, and follow-up visits with health care provider.
Nursing Process—Client Receiving an Antitubercular Drug #12
Evaluation
Was the therapeutic response achieved? No evidence of infection?
Were adverse reactions: identified, reported, and managed?
No evidence of injury
Client maintains adequate nutrition status
Client manages the therapeutic regimen effectively
Did client and family express confidence and demonstrate understanding of drug regimen?
Turn and Talk—Case Study
A 55-year-old client came to the physician’s office 2 days ago with a 2-week history of coughing, sputum production, and night sweats. The nurse administered a PPD skin test at that time. The client returns today for the nurse to read the PPD skin test. The skin test is positive, and the physician diagnoses the client with tuberculosis.
What preadministration assessment should be completed before starting the client on any antitubercular drugs?
What ongoing assessment should the nurse conduct while the client is taking the antitubercular drugs?
What are three ways the nurse can increase the client's compliance with the antitubercular treatment regimen?