What are second line drugs?

Second line drugs refer to medications used to treat conditions when first-line treatments are ineffective, intolerable, or contraindicated. In the context of Infectious Diseases, particularly tuberculosis and HIV, second line drugs are typically more complex, less effective, and may have more side effects compared to first-line options. They are often reserved for cases of drug resistance or when patients do not respond to initial therapy. The choice of second line treatment depends on the specific disease and the patient's individual circumstances.