Pyridine (phenazopyridine) is a medication used to relieve pain, burning, and discomfort associated with urinary tract infections. It can relieve symptoms but does not treat the infection itself. Available in the US without a prescription in our online store, Fast and reliable shipping. Pyridine works quickly to relieve pain and its effect lasts up to 2 hours. It is recommended that you drink plenty of water while taking this medication to help flush the infection out of your system.