Phenazopyridine
PYRIDIUM
What it isUrinary tract analgesic acting locally on mucosa; dysuria.
Why this oneIt relieves dysuria within hours while an antibiotic takes effect.
What limits itIt treats no infection and masks symptoms, so it is limited to two days. Orange discoloration stains contact lenses; methemoglobinemia.
FDA-approved for
- urinary pain (~1950)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Urinary tract pain/irritation | Adult | 200 mg TID after meals |
Renal Contraindicated in renal insufficiency
Hepatic Undefined
When used with an antibacterial for UTI, limit concomitant use to 2 days.
Instructions
- Take after meals
- When combined with an antibacterial for UTI, do not exceed 2 days of concomitant use
Contraindications
- Renal insufficiency
Cautions
- Methemoglobinemia and hemolytic anemia (esp. overdose or renal impairment)
- Renal and hepatic toxicity reported at overdose levels
Adverse reactions
- Headache, rash, pruritus, GI disturbance
- Methemoglobinemia, hemolytic anemia
- Anaphylactoid-like reaction
Pregnancy Animal studies show no fetal harm; no adequate human studies — use only if clearly needed.
Lactation Undefined
NO BOXED WARNINGS
Principal riskIt masks symptoms and treats no infection; limit to two days
Cost, est. cash$10–$300/month
Generic entryPre-1982
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
Mechanism of action: Phenazopyridine ballicule
