Phenazopyridine: Uses, Warnings, Side Effects, Interactions, Dosage and Overdosage

It is a medicine used to relieve symptoms caused by urinary tract irritation, such as pain, burning, and the urge to urinate urgently or frequently.

It can also treat other discomforts in the lower urinary tract caused by trauma, surgery, endoscopic procedures, or catheters.

You should not take phenazopyridine for more than two days. There is no evidence that the combined effect of phenazopyridine and an antibacterial provides a more significant benefit than administering antibacterial alone after those two days.

Phenazopyridine was discovered by Bernhard Joos, the founder of Cilag.


Do not take this medication if you are allergic to pyridinium or have kidney disease, liver disease, or other blood disorders. This drug will make your urine dark or change it to an orange or red color. This is an average effect and is no cause for alarm.

If you wear contact lenses, you should stop using them while receiving treatment with the medication. It is known that the drug permanently discolors contact lenses (and fabrics used to manufacture underwear).

If you have diabetes, consider that phenazopyridine can cause false results in urine blood sugar testing and ketone testing. You should ask your doctor what to do, primarily if your diabetes is poorly controlled. Unless your doctor has told you to, do not use phenazopyridine for more than two days.


This medicine can make you dizzy. Do not drive, use machinery, or perform activities that require alertness until you are sure you can achieve those activities safely.

Phenazopyridine is eliminated from your body by the kidneys. As you get older, your kidney function may decrease significantly. Older people may have an increased risk of change in the amount of urine or yellow skin, or eyes if treated with phenazopyridine.

Pregnancy and phenazopyridine

You should inform your doctor if you are pregnant before using this medicine. It has not shown any adverse effects in pregnant animals, but no trials have been conducted in humans.

It is not known if this medication passes into breast milk. But you should consult your doctor before breastfeeding if you are being treated with this drug.

Side effects

Common side effects of phenazopyridine:

Some of the side effects may not need medical attention. As your body gets used to the medication, these side effects will disappear:

  • Dizziness.
  • Headache.
  • Indigestion.
  • Itching of the skin
  • Stomach cramps or pain

Serious side effects of phenazopyridine:

If you have any of the following side effects while taking phenazopyridine, stop using the medication and check with your doctor or nurse as soon as possible:

  • Blue or violet-blue color of the skin.
  • Fever and confusion
  • Short of breath.
  • Wheezing or difficulty breathing
  • Acne.
  • A sudden decrease in the amount of urine.
  • Swelling of face, fingers, feet, and calves.
  • Unusual tiredness or weakness
  • Weight gain.
  • Yellow eyes or skin

Get emergency medical help if you have any signs of an allergic reaction, which includes:

  • Urticaria.
  • Difficult breathing
  • Swelling of your face, lips, tongue, or throat.


There may be other drugs that can affect pyridium. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and recreational drugs. Do not start using any new medicine without telling your doctor.

If your doctor prescribes phenazopyridine, it should only be used for your current condition. Please do not take it later for another state related to urinary tract pain unless your doctor tells you to. Other medication may be necessary in those cases.

You should avoid drinking alcohol while taking phenazopyridine.


Typical dose:

Phenazopyridine comes in 100 mg and 200 mg tablets. It works better in the stomach if you take it with food or after eating or snack. The usual dose is a tablet that is taken three times a day.

If you take this medication and antibiotics to treat symptoms related to a urinary tract infection, or if you are treating yourself, do not take it for more than two days without talking to your doctor. If your condition persists or worsens, inform your doctor immediately.

Without consulting your doctor, you should not store any extra medication for future urinary tract problems. Recurrent infection may require additional medications.


If you think you have used too much phenazopyridine, you should seek immediate emergency medical attention.

Symptoms of an overdose may include:

  • Yellow or blue skin.
  • Fever.
  • Confusion.
  • Weakness.
  • Urinating less than usual.
  • Nausea or vomiting
  • Swelling or numbness

Exceeding the recommended dose may cause kidney failure, especially if you are an older adult.

Missed dose of phenazopyridine

If you miss a dose of phenazopyridine, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take medicine at your next dose.