Browse Medications by Medical Condition: Tuberculosis (TB)

Tuberculosis (TB) is a contagious bacterial infection primarily affecting the lungs, but it can also affect other parts of the body such as the kidneys, spine, or brain. It is caused by the bacterium Mycobacterium tuberculosis. TB spreads through the air when an infected person coughs, sneezes, or talks, releasing tiny droplets containing the bacteria. While some people may carry the bacteria without showing symptoms, others develop active TB, characterized by coughing, weight loss, night sweats, and fatigue. If left untreated, TB can cause serious health complications, including lung damage and even death. TB is a global health concern, especially in low- and middle-income countries, but it is treatable with antibiotics when caught early.

Tuberculosis has been recognized for thousands of years, with evidence of the disease found in ancient Egyptian mummies. It was once called "consumption" due to the weight loss and wasting associated with the disease. In the 19th century, TB was a leading cause of death, particularly in urban areas with crowded living conditions. The discovery of Mycobacterium tuberculosis by Robert Koch in 1882 marked a significant milestone in understanding the disease. Following Koch's discovery, diagnostic techniques, such as the tuberculin skin test, were developed. The introduction of the first effective antibiotic for TB, streptomycin, in the 1940s greatly improved treatment. However, the rise of drug-resistant TB in recent decades poses a major challenge to global TB control efforts.

Tuberculosis is caused by the bacterium Mycobacterium tuberculosis, which typically enters the body through the lungs when an infected person coughs or sneezes. The bacteria then travel to the lungs, where they can remain dormant in some individuals, causing latent TB infection. In those with weakened immune systems, the bacteria may become active, leading to active TB disease. Factors such as close contact with infected individuals, living in crowded conditions, having a compromised immune system (due to conditions like HIV, diabetes, or malnutrition), and smoking increase the risk of developing active TB. Additionally, people in healthcare settings or regions with high TB rates are at greater risk.

The primary risk factors for tuberculosis include a weakened immune system, such as in people living with HIV, diabetes, or undergoing immunosuppressive treatments. People living in or traveling to regions with high TB rates (including sub-Saharan Africa, Southeast Asia, and parts of Eastern Europe) are at higher risk. Other factors include living in crowded or poor conditions, working in healthcare or correctional facilities, being an intravenous drug user, and smoking, which can damage the lungs and make them more susceptible to infection. Older adults and young children also have a higher vulnerability to the disease.

Preventing TB involves reducing exposure to the bacteria, particularly in high-risk settings. People with active TB should adhere to prescribed treatment and avoid close contact with others until they are no longer infectious. Vaccination with the Bacillus Calmette-Guerin (BCG) vaccine is commonly used in countries with high TB prevalence, especially for children, though it is not 100% effective. Good hygiene practices, such as covering the mouth when coughing, improving ventilation in crowded spaces, and wearing masks, are also important preventive measures. For people at high risk, including those with HIV or a history of TB exposure, preventive treatment with antibiotics may be recommended to prevent the development of active disease.

The symptoms of active tuberculosis include a persistent cough lasting more than three weeks, often accompanied by chest pain. Other common signs include unexplained weight loss, night sweats, fever, chills, fatigue, and coughing up blood or mucus. TB can also cause shortness of breath and a general feeling of illness. In cases of extrapulmonary TB (when the infection affects organs other than the lungs), symptoms vary depending on the area of the body involved, such as swelling or pain in the bones, or neurological symptoms if the brain is affected.

Tuberculosis is diagnosed using a combination of medical history, physical examination, and laboratory tests. The most common diagnostic test is a chest X-ray, which can detect lung damage caused by TB. A sputum test, in which a sample of mucus from the lungs is examined under a microscope, can identify the presence of Mycobacterium tuberculosis bacteria. A tuberculin skin test, or Mantoux test, can indicate exposure to TB, but it cannot confirm active disease. In some cases, molecular tests or culture tests may be used to confirm the diagnosis, especially in drug-resistant TB cases.

Treatment for tuberculosis involves a course of antibiotics, typically lasting six months, to kill the bacteria and prevent the development of drug-resistant strains. The first-line medications for TB include isoniazid, rifampin, pyrazinamide, and ethambutol. Patients with drug-resistant TB may need second-line medications, which are often more complex and require a longer treatment period. Directly observed therapy (DOT), where a healthcare provider supervises the patient taking their medication, is often recommended to ensure adherence to the treatment regimen and prevent the emergence of drug resistance. Early diagnosis and consistent treatment are key to curing TB and preventing its spread.

The primary medications used to treat tuberculosis include isoniazid, rifampin, pyrazinamide, and ethambutol. These antibiotics work together to kill the bacteria and prevent resistance. In cases of multidrug-resistant TB (MDR-TB) or extensively drug-resistant TB (XDR-TB), second-line drugs like kanamycin, amikacin, and linezolid may be prescribed. Antibiotics may need to be taken for a longer duration (up to 24 months for some resistant strains). It is essential for patients to complete the full course of treatment to avoid relapse and the development of resistant TB strains.

Managing tuberculosis involves adhering to the prescribed medication regimen and following health guidelines to prevent spreading the disease. Patients with TB should rest and maintain good nutrition to help their bodies fight the infection. It's also crucial to avoid close contact with others, especially in the initial phase of treatment, until they are no longer contagious. Quitting smoking, improving indoor ventilation, and following hygiene practices such as covering the mouth when coughing can help reduce the spread of the disease. Patients may also need regular follow-up visits to monitor their progress and check for potential drug resistance.

The direct costs of tuberculosis include medical expenses for diagnostic tests, medications, and healthcare visits. For patients with drug-resistant TB, treatment can be more expensive due to longer courses of more complex medications. In addition to healthcare costs, there may be indirect costs, such as lost income due to the inability to work during the illness and recovery. The societal costs of TB also include public health efforts to control and prevent the spread of the disease, which can place a significant burden on healthcare systems, especially in low-resource settings.

Living with tuberculosis requires a commitment to treatment and adherence to prescribed medications for an extended period, often six months or longer. Patients may experience side effects from the medications, such as nausea, liver toxicity, or peripheral neuropathy, which should be monitored by a healthcare provider. Regular medical follow-up is important to ensure the infection is fully treated and to check for potential complications. TB patients also need to take precautions to avoid transmitting the disease to others, including maintaining good hygiene and avoiding close contact during the contagious phase.

There are various resources available for individuals living with tuberculosis, including local and national tuberculosis organizations. The World Health Organization (WHO) provides global guidelines on TB prevention, diagnosis, and treatment. The Centers for Disease Control and Prevention (CDC) also offers educational materials and support for patients in the U.S. Additionally, patient support groups, such as those organized by TB charities or nonprofit organizations, can provide emotional support, information, and access to healthcare resources.

Research into tuberculosis is focused on improving diagnostic methods, developing more effective vaccines, and finding better treatments for drug-resistant strains. New molecular diagnostics are being developed to detect TB faster and more accurately, particularly in resource-limited settings. Advances in vaccine research, such as the development of more effective TB vaccines, hold promise for reducing the global burden of the disease. Researchers are also working on novel therapies that target drug-resistant TB, and innovations in drug development may lead to shorter treatment regimens. The goal of eliminating TB as a global public health threat by 2035 remains a key focus of research.

Innovations in tuberculosis care include new diagnostic tools like rapid molecular tests and portable devices that can detect TB in a matter of hours. New medications are being tested to shorten the duration of treatment and improve the effectiveness of therapy, particularly for multidrug-resistant TB. In addition, better vaccines and immunotherapies are being explored to prevent infection and reduce the transmission of TB. Digital health technologies, such as telemedicine and mobile apps, are also being used to improve treatment adherence and monitoring, especially in remote areas with limited access to healthcare.