Phenazopyridine HCL

Phenazopyridine Hydrochloride is indicated for the symptomatic relief of pain, burning, urgency frequency, and other discomforts arising from irritation of the mucosa of the lower urinary tract caused by infection, trauma, surgery, endoscopic procedures, or the passage of sounds or catheters. The use of Phenazopyridine Hydrochloride for relief of symptoms should not delay definitive diagnosis and treatment of causative conditions.

The drug should be used for symptomatic relief of pain and not as a substitute for specific surgery or antimicrobial therapy. Phenazopyridine Hydrochloride is compatible with antimicrobial therapy and can help relieve pain and discomfort during the interval before antimicrobial therapy controls the infection. Treatment of a urinary tract infection with Phenazopyridine Hydrochloride should not exceed 2 days. There is no evidence that the combined administration of Phenazopyridine Hydrochloride and an antimicrobial provides greater benefit than administration of the antimicrobial alone after 2 days.

(See DOSAGE AND ADMINISTRATION.)

Phenazopyridine Hydrochloride should not be used in patients who are hypersensitive to the drug or its ingredients. Phenazopyridine Hydrochloride is contraindicated in patients with renal insufficiency, severe liver disease, severe hepatitis or pyelonephritis of pregnancy. It should be used cautiously in the presence of GI disturbances.

Phenazopyridine Hydrochloride is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals (IARC 1980, 1982, 1987, NCI 1978). When administered in the diet, Phenazopyridine hydrochloride increased the incidences of hepatocellular adenomas and carcinomas in female mice and adenomas and adenocarcinomas of the colon and rectum in rats of both sexes. There is inadequate evidence for the carcinogenicity of Phenazopyridine hydrochloride in humans (TARC 1987).

In one limited epidemiological study, no significant excess of any cancer was observed among 2,214 patients who received Phenazopyridine hydrochloride and were followed for a minimum of 3 years.

The following adverse events have been reported: CNS: headache. Gastrointestinal: nausea, vomiting and diarrhea. Dermatologic and Hypersensitivity: rash, pruritus, discoloration, anaphylactoid-like reaction and hypersensitivity hepatitis. Hematologic: methemoglobinemia, hemolytic anemia, potential hemolytic agent in G-6-PD deficiency, sulfhemoglobinemia. Other: visual disturbances, renal and hepatic toxicity usually associated with overdose, renal calculi, jaundice, discoloration of body fluids and aseptic meningitis.