Phenazopyridine

Key facts

• Phenazopyridine (sold as Pyridium and other brands) is a urinary analgesic. It numbs the lining of the bladder and urethra but has no antibacterial action.
• It only relieves pain; it does not treat a urinary tract infection, so keep taking any antibiotic your prescriber has given you alongside it.
• Limit use to 2 days unless a doctor tells you otherwise. Longer use can mask a worsening or untreated infection and delay diagnosis.
• Seek urgent care for yellowing of the skin or eyes, a bluish-grey skin tone, or very little urine output.

What phenazopyridine treats

Phenazopyridine relieves the burning, urgency and discomfort of a urinary tract infection, and soreness after urologic procedures. It treats the symptom only, not the infection, so it's normally used alongside an antibiotic and stopped once the pain has settled, usually within 2 days.

How phenazopyridine works

The drug is absorbed and then excreted into the urine, where it has a local numbing effect on the bladder and urethral lining. This dulls the pain and urgency signals without acting on the bacteria causing them.

Before you take it

• Do not use it if you have kidney disease with reduced urine output, or a known allergy to phenazopyridine.
• Tell your prescriber if you have G6PD deficiency, an inherited enzyme condition. Phenazopyridine can trigger breakdown of red blood cells (hemolysis) in people with this condition.
• It stains urine, and sometimes sweat or tears, orange to red. This is harmless but can permanently mark fabric and discolor soft contact lenses, so remove lenses before use.
• Do not use it for more than 2 days without medical advice, and don't rely on it to repeatedly self-treat urinary symptoms without seeing a doctor.

Side effects

Common effects are headache, dizziness, stomach upset, and orange-red urine, which is expected and harmless.

Seek urgent medical care for:

• Yellowing of the skin or eyes, or pale stools, which can signal liver injury.
• Bluish-grey skin or lips, shortness of breath, or unusual tiredness, which can signal methemoglobinemia, a blood disorder that reduces oxygen delivery.
• Very little or no urine output.
• Signs of an allergic reaction: rash, swelling, difficulty breathing.

Safety essentials

• Phenazopyridine is a symptom reliever only. It does not cure infection, and using it for more than 2 days can mask worsening disease, so see a doctor if pain continues.
• People with G6PD deficiency or significant kidney impairment should avoid it, since it raises the risk of hemolysis and can build up to toxic levels.
• Expect orange-red urine. Tell your lab technician before a urine test, since the colour can interfere with results, and keep it away from contact lenses and light-coloured clothing.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.