Generic name: phenazopyridine
Brand names: Azo Urinary Pain Relief, Azo Urinary Pain Relief Maximum Strength
Dosage form: tablets (95mg, 99.5mg)
Drug class: Miscellaneous genitourinary tract agents

Medically reviewed by Melisa Puckey, BPharm. Last updated on Feb 4, 2024.

What is Azo?

Azo is used to relieve symptoms of a urinary tract infection (UTI) to help with pain or burning, urgency, and frequency of urinating. Azo pills are available as Azo Urinary Pain Relief which contains 95mg phenazopyridine, and the Azo Urinary Pain Relief Maximum Strength, which contains 99.5mg phenazopyridine.

If you have symptoms including urinary pain, burning, urgency, and frequency, it may indicate you have a urinary tract infection. It is important to call your doctor to get a diagnosis and obtain a prescription to treat the infection. While you wait to get to the doctor and for the prescription to begin to work, Azo may help relieve your UTI symptoms.

Azo is used to help urinary symptoms, but this medication will not treat a urinary tract infection. Take an antibiotic that your doctor prescribes to treat an infection.

Azo side effects

Common Azo side effects may include headache, dizziness, or upset stomach.

Serious Azo side effects

Get emergency medical help if you have any of these signs of an allergic reaction hives, difficulty breathing, swelling of your face, lips, tongue, or throat.

Azo may cause other serious side effects. Stop using Azo and call your doctor at once if you have:

• little or no urinating;
• swelling, rapid weight gain;
• confusion, loss of appetite, pain in your side or lower back;
• fever, pale or yellowed skin, stomach pain, nausea and vomiting; or
• blue or purple appearance of your skin.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

Ask a doctor before use if you have:

• liver or kidney trouble
• allergies to foods, preservatives, or dyes
• had a hypersensative reaction to Phenazopyridine Hydrochloride

Before taking this medicine

You should not use Azo if you are allergic to it or if you have kidney disease.

To make sure Azo is safe for you, tell your doctor if you have liver disease or diabetes.

Do not use Azo if you have a genetic enzyme deficiency called glucose-6-phosphate dehydrogenase (G6PD) deficiency unless approved by your physician.

Pregnancy

FDA pregnancy category B. Azo is not expected to harm an unborn baby but do not use it without a doctor's advice if you are pregnant.

Breastfeeding

It is not known whether Azo passes into breast milk or if it could harm a nursing baby. Do not use this medicine without a doctor's advice if you are breastfeeding a baby.

How should I take Azo?

Use exactly as directed on the label or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Take Azo with or after meals. Drink plenty of liquids while you are taking this medicine.

Do not use this medicine for longer than 2 days unless your doctor has told you to.

General Azo information

Azo will most likely darken the color of your urine to an orange or red color. This is a normal effect and is not harmful. Darkened urine may also cause stains to your underwear that may be permanent.

Azo can also permanently stain soft contact lenses, and you should not wear them while taking this medicine.

This medication can cause unusual results with laboratory tests, including urine, glucose (sugar), and ketones tests. Tell any doctor who treats you that you are using Azo if you are having any tests done.

Azo dosing information

Usual dose for Azo Urinary Pain Relief Tablet for UTI symptoms

Adults and children over 12 years old: Take 2 tablets 3 times a day with or after meals as needed for up to two days. Take with a full glass of water. Do not use for more than 2 days (12 tablets) without consulting a doctor.

Usual adult dose for Azo Urinary Pain Relief Maximum Strength Tablet for UTI symptoms

Adults and children over 12 years old Take 2 tablets 3 times a day with or after meals as needed for up to two days. Take with a full glass of water. Do not use for more than 2 days (12 tablets) without consulting a doctor.

Comments:
This drug should not be used longer than 2 days concomitantly with an antibacterial, because of the lack of evidence that the combined administration of this drug and an antibacterial provides greater benefit than the antibacterial alone after 2 days.

Related/similar drugs

oxybutynin, phenazopyridine, Pyridium, imipramine, Ditropan, Elmiron, Ditropan XL, flavoxate, dimethyl sulfoxide, pentosan polysulfate sodium

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Azo?

Do not use Azo Urinary Pain Relief or Azo Urinary Pain Relief Maximum Strength while wearing soft contact lenses. Phenazopyridine can permanently discolor soft contact lenses.

What other drugs will affect Azo?

Other drugs may interact with Azo, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your healthcare providers about all the medicines you use now and any medicines you started or stop using.

Ingredients

Active Ingredient: Phenazopyridine

Azo Urinary Pain Relief Maximum Strength Inactive Ingredients: carnauba wax, croscarmellose sodium, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, povidone, pregelatinized corn starch. May also contain corn starch.

Azo Urinary Pain Relief Inactive ingredients: microcrystalline cellulose, pregelatinized corn starch, hypromellose, povidine, croscarmellose sodium, polyethylene glycol, carnauba wax and vegetable magnesium stearate. May also contain corn starch.

Storage

Store at room temperature (59° - 86°F) in a dry place and protect from light.

Frequently asked questions

• Why do you not take phenazopyridine for more than two days?

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer