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Medication Safety Issues

Sound-alike/look-alike issues:

Phenazopyridine may be confused with phenoxybenzamine

Pyridium® may be confused with Dyrenium®, Perdiem®, pyridoxine, pyrithione

Pronunciation

(fen az oh PEER i deen)

U.S. Brand Names

• AZO-Gesic® [OTC]
• AZO-Standard® Maximum Strength [OTC]
• AZO-Standard® [OTC]
• Baridium® [OTC]
• Prodium® [OTC]
• Pyridium®
• ReAzo [OTC]
• UTI Relief® [OTC]

Index Terms

• Phenazopyridine Hydrochloride
• Phenylazo Diamino Pyridine Hydrochloride

Generic Available

Yes

Canadian Brand Names

• Phenazo™

Pharmacologic Category

• Analgesic, Urinary

Pharmacologic Category Synonyms

• Urinary Analgesic

Use: Labeled Indications

Symptomatic relief of urinary burning, itching, frequency and urgency in association with urinary tract infection or following urologic procedures

Pregnancy Risk Factor

B

Lactation

Excretion in breast milk unknown

Contraindications

Hypersensitivity to phenazopyridine or any component of the formulation; kidney or liver disease; patients with a Cl_cr <50 mL/minute

Warnings/Precautions

Concerns related to adverse effects:

• Yellow discoloration: Drug should be discontinued if skin or sclera develop a yellow color.

Disease-related concerns:

• Renal impairment: Use with caution in patients with renal impairment; use is contraindicated in patients with a Cl_cr <50 mL/minute.

Special populations:

• Elderly: Use of this agent in the elderly is limited since accumulation can occur in patients with renal insufficiency.

Other warnings/precautions:

• Limitations of use: Does not treat urinary infection, acts only as an analgesic.

Adverse Reactions

1% to 10%:

Central nervous system: Headache, dizziness

Gastrointestinal: Stomach cramps

<1%: Acute renal failure, methemoglobinemia, hemolytic anemia, hepatitis, rash, skin pigmentation, vertigo

Drug Interactions

There are no known significant interactions.

Mechanism of Action

An azo dye which exerts local anesthetic or analgesic action on urinary tract mucosa through an unknown mechanism

Pharmacodynamics/Kinetics

Metabolism: Hepatic and via other tissues

Excretion: Urine (65% as unchanged drug)

Dosage

Oral:

Children: 12 mg/kg/day in 3 divided doses administered after meals for 2 days

Adults: 100-200 mg 3 times/day after meals for 2 days when used concomitantly with an antibacterial agent

Dosing interval in renal impairment:

Cl_cr 50-80 mL/minute: Administer every 8-16 hours

Cl_cr <50 mL/minute: Avoid use

Administration: Oral

Administer after meals.

Test Interactions

Phenazopyridine may cause delayed reactions with glucose oxidase reagents (Clinistix®, Tes-Tape®); occasional false-positive tests occur with Tes-Tape®; cupric sulfate tests (Clinitest®) are not affected; interference may also occur with urine ketone tests (Acetest®, Ketostix®) and urinary protein tests; tests for urinary steroids and porphyrins may also occur

Dietary Considerations

Should be taken after meals.

Patient Education

Take exactly as directed. May discolor urine (orange/yellow); this is normal, but will also stain fabric. If you have diabetes, use serum glucose tests; this medication may interfere with accuracy of urine testing. Report persistent headache, dizziness, or stomach cramping. Breast-feeding precaution: Consult prescriber if breast-feeding.

Geriatric Considerations

Use of this agent in older adults is limited since accumulation of phenazopyridine can occur in patients with renal insufficiency.

Dental Health: Effects on Dental Treatment

No significant effects or complications reported

Dental Health: Vasoconstrictor/Local Anesthetic Precautions

No information available to require special precautions

Mental Health: Effects on Mental Status

May cause dizziness

Mental Health: Effects on Psychiatric Treatment

None reported

Nursing: Physical Assessment/Monitoring

Assess therapeutic effectiveness (according to rationale for use). Instruct patients with diabetes to use serum glucose monitoring (phenazopyridine may interfere with certain urine testing reagents). Teach patient appropriate use, side effects/appropriate interventions, and adverse symptoms to report..

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Tablet, as hydrochloride: 100 mg, 200 mg

AZO-Gesic®, Prodium®, ReAzo: 95 mg

AZO-Standard®: 95 mg [gluten free]

AZO Standard® Maximum Strength: 97.5 mg [gluten free]

Baridium®, UTI Relief®: 97.2 mg

Pyridium®: 100 mg, 200 mg

Pricing: U.S. (www.drugstore.com)

Tablets (Phenazopyridine HCl)

100 mg (30): $13.99

200 mg (30): $18.77

Tablets (Pyridium)

100 mg (30): $35.99

200 mg (30): $63.41

International Brand Names

• Anazo (TH)
• Azo Cefasabal (PE)
• Cistalgina (AR)
• CP-Pyridine (HK)
• Nefrecil (PL)
• Phenazo (HK)
• Phendiridine (TH)
• Pirimir (MX)
• Pyredal (NO)
• Pyridium (AE, BF, BH, BJ, BR, CI, CN, CR, CY, DE, EG, ES, ET, FR, GH, GM, GN, GT, HK, HN, IL, IN, IQ, IR, JO, KE, KW, LB, LR, LY, MA, ML, MR, MU, MW, NE, NG, NI, OM, PA, PE, QA, SA, SC, SD, SL, SN, SV, SY, TN, TZ, UG, UY, VE, YE, ZA, ZM, ZW)
• Pyronium (BE)
• Sedural (IL)
• Tiotal (PY)
• Urogen (TW)
• Urogesic (SG)
• Urogetix (ID)
• Uroprin (TW)
• Uropyrin (TW)
• Uropyrine (BE)
• Uroxacin (CO)

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Last full review/revision November 2009

Content last modified November 2009