Nal salt, or sodium nalidixate, is a medication primarily used as an antibiotic for the treatment of urinary tract infections caused by certain bacteria. It works by inhibiting bacterial DNA synthesis, which ultimately stops the growth of bacteria.
It's important to note that sodium nalidixate is not widely used today due to the development of newer antibiotics that are more effective and have fewer side effects. As always, it's essential to consult a healthcare professional for appropriate diagnosis and treatment options for infections.