What Is a Diuretic?

By Amanda Doyle
Reviewed by Claudia Levi, R.N.
September 08, 2025

A diuretic is a type of medication that doctors may prescribe for high blood pressure. It may also be called a “water pill.” Diuretics help your body get rid of salt and water by excreting it through your urine. As a result, blood pressure may go down.

Diuretics come with a risk of several side effects, including:

  • Frequent urination
  • Dehydration
  • Low sodium levels in the body
  • Headaches
  • Muscle cramps

Be sure to speak with your healthcare provider before taking diuretic medication. There’s a variety of blood pressure medication options to consider. Your unique health history and condition will help you and your doctor make an informed decision about the best treatment for you.