Directly Observed Therapy:
Information for Health Care Providers
TB Fact Sheet 2a
Directly Observed Therapy (DOT) is the standard of care for tuberculosis (TB) treatment.1 In directly observed therapy, a trained health care worker monitors the patient taking each dose of anti-tuberculosis medication. When TB patients receive all medications as prescribed under a program of DOT, both patients and community benefit.
- • Response to therapy is closely monitored
- • Patients complete therapy2
- • Survival may improve in patients infected with the human immunodeficiency virus (HIV), because DOT ensures treatment for TB3
- • Rates of drug resistance in the community decrease4,5
Intermittent therapy by DOT
For fully drug-susceptible TB, treatment given two or three times per week by DOT is at least as effective as daily treatment.6,7,8 This schedule makes adherence easier for the patient, and, because the patient receives the same benefit from a smaller amount of medicine, intermittent therapy may also reduce drug side effects.
When DOT is imperative
DOT can prevent the transmission of TB and help safeguard patients on regimens that pose a high risk of drug interactions. Therefore, DOT is essential in the presence of any of the following:
- • Pulmonary TB that is smear-positive for acid-fast bacilli -- these patients, if not on DOT, represent a potential risk to the public health
- • Multidrug-resistant strains of TB9
- • Concurrent treatment with antiretroviral drugs or methadone10
Referring TB patients for DOT
The New York City Department of Health and Mental Hygiene (NYC DOHMH ) provides DOT in its clinics, as well as in patients' homes and workplaces whenever necessary. Many other facilities in New York City also provide DOT. To refer a patient for DOT, contact the NYC DOHMH, Bureau of TB Control, Network Field Offices, at 311.
- • The physician who decides not to place a patient on DOT assumes responsibility for ensuring adherence and completion. It is unwise to assume that patients will take medications on their own.11
- • Directly observed treatment of latent TB infection can be arranged by the NYC DOHMH for certain high-risk persons (e.g., children of DOT patients, or some HIV-infected persons).
Non-adherence to therapy on DOT
If a patient keeps fewer than 80% of appointments for DOT, one or more of the following steps can be taken to improve adherence:
- • Reasonable avenues that foster adherence can be explored, such as referrals for social work, housing, or detoxification and attention to medication schedules or side effects.
- • Culturally appropriate education explaining the rationale for DOT can be provided for foreign-born patients.
- • A Commissioner's Order for Directly Observed Therapy (CODOT) can be served in difficult cases. CODOTs are very effective in ensuring adherence, even for patients with life challenges such as addiction and homelessness.
- • As a last resort - and this is rarely necessary - action can be taken to detain a patient until an adequate course of treatment is completed.
For assistance in dealing with difficult cases of non-adherence to therapy, call the Bureau of TB Control, Regulatory Affairs Office, at 311.
Notes and References
- • Fujiwara PI, Larkin C, Frieden TR. Directly observed therapy in New York City: history, implementation, results, and challenges. Clin Chest Med. 1997;18(1):135-48.
- • More than 90% of patients diagnosed with TB and treated in New York City since 1994 complete therapy, compared with fewer than 50% in the late 1980s, before DOT became the standard of care.
- • Alwood K, Keruly J, Moore-Rice K, et al. Effectiveness of supervised, intermittent therapy for tuberculosis in HIV-infected patients. AIDS 1994;8:1103-8.
- • Weis SE, Slocum PC, Blais FX, et al. The effect of directly observed therapy on the rates of drug resistance and relapse in tuberculosis. New Engl J Med 1994;330:1179-84.
- • Murray BE. Can antibiotic resistance be controlled? (Editorial) N Engl J Med 1994;330:1229-30.
- • Hong Kong Chest Service/British Medical Research Council. Controlled trial of 4 three-times-weekly regimens and a daily regimen all given for 6 months for pulmonary tuberculosis. Second report: the results up to 24 months. Tubercle 1982;63:89-98.
- • Hong Kong Chest Service/British Medical Research Council. Five-year follow-up of a controlled trial of five 6-month regimens of chemotherapy for pulmonary tuberculosis. Am Rev Respir Dis 1987;136:1334-42.
- • Cohn DL, Catlin BJ, Peterson KL, et al. A 62-dose 6-month therapy for pulmonary and extrapulmonary tuberculosis. Ann Intern Med 1990;112:407-15.
- • NYC DOHMH, Bureau of TB Control. TB Fact Sheet 4c: Multidrug-resistant TB.
- • NYC DOHMH, Bureau of TB Control. TB Fact Sheet 2k: Antiretroviral drugs and the treatment of TB. For the methadone/rifampin interaction, see TB Fact Sheet 2d: The importance of rifampin.
- • The Tuberculosis Control Program has learned from pharmacies that many patients fail to fill prescriptions for anti-TB medications.
Related Publications
For further information, call 311.
