phenazopyridine (Azo Standard, Pyridium, Prodium, Pyridiate, Baridium, Uricalm, Urodine, UTI Relief)
Classes: Analgesics, Urinary
Dosing and uses of Azo Standard, Pyridium (phenazopyridine)
Adult dosage forms and strengths
tablets
- 95mg
- 97.2mg
- 100mg
- 200mg
Dysuria, Irritation of Lower Urinary Tract Mucosa
100-200 mg PO after meals three times daily
Dosing considerations
- When used concomitantly with antibiotic for UTI, do not use for longer than 2 days
- Limit dosing in geriatric population due to decreased renal function
Administration
Give after food/meals to minimize GI side effects
Pediatric dosage forms and strengths
tablets
- 95mg
- 97.2mg
- 100mg
- 200mg
Dysuria, Irritation of Lower Urinary Tract Mucosa
<6 years: Safety and efficacy not established
6-12 years: 12 mg/kg/day PO after meals, divided q8hr
>12 years: 100-200 mg PO after meals three times daily
Dosing considerations
- When used concomitantly with antibiotic for UTI, do not use for longer than 2 days
Administration
Give after food/meals to minimize GI side effects
Azo Standard, Pyridium (phenazopyridine) adverse (side) effects
Frequency not defined (Rare)
Headache
Vertigo
Rash
Pruritus
Mild GI disturbances
Methemoglobinemia
Hemolytic anemia
Skin pigmentation
Transient ARF
Renal calculi
Staining of contact lenses
Hepatic/renal toxicity
Warnings
Contraindications
Hypersensitivity
Renal impairment (CrCl <50mL/min)
Cautions
Changes urine color; may affect UA based on spectrometry or color reactions
May stain contact lenses
Discontinue if yellowish color of skin or sclera, as this is an indication of drug accumulation due to renal failure; monitor geriatric patients due to greater risk
Self-medication should not continue >2 days; if pain persists, consult physician
Intended as analgesic, not for treatment of UTI
Use caution in patients with G6PD deficiency; hemolytic anemia may occur in the setting of chronic overdose
Not for treatment of urinary inferction; acts only as analgesic
Discontinue over the counter use if symptoms last more than 2 days or adverse effects occur
May stain fiber or clothing
Pregnancy and lactation
Pregnancy category: B
Lactation: Not known if excreted in breast milk; exercise caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Azo Standard, Pyridium (phenazopyridine)
Mechanism of action
Azo dye; acts directly on urinary tract mucosa when excreted, to produce local analgesic effect
Metabolism
Metabolized by liver
Elimination
Excretion
- Urine: Eliminated mainly through rapid excretion by kidneys (65% unchanged)
- Feces: Minor amount