For definition of Groups, see Preamble Evaluation.
Supplement 7: (1987) (p. 312)
Chem. Abstr. Name: 2,6-Pyridinediamine,3-(phenylazo)-,monohydrochloride
A. Evidence for carcinogenicity to humans (inadequate)
In one limited epidemiological study, no significant excess of any cancer was observed among 2214 patients who received phenazopyridine hydrochloride and were followed for a minimum of three years [ref: 1].
B. Evidence for carcinogenicity to animals (sufficient)
Oral administration of phenazopyridine hydrochloride increased the incidence of hepatocellular adenomas and carcinomas in female mice and induced tumours of the colon and rectum in rats [ref: 1].
C. Other relevant data
No data were available on the genetic and related effects of phenazopyridine hydrochloride in humans. It did not induce sex-linked recessive lethal mutations in Drosophila and was not mutagenic to bacteria [ref: 2].
Phenazopyridine hydrochloride is possibly carcinogenic to humans (Group 2B).
For definition of the italicized terms, see Preamble Evaluation.
Also see previous evaluations: Vol. 8 (1975); Vol. 24 (1980)
1. IARC Monographs, 24, 175-184, 1980
2. IARC Monographs, Suppl. 6, 451-452, 1987
See Also: Toxicological Abbreviations Phenazopyridine Hydrochloride (IARC Summary & Evaluation, Volume 8, 1975)