International Agency for Research on Cancer (IARC) - Summaries & Evaluations

(Group 3)

For definition of Groups, see Preamble Evaluation.

VOL.: 50 (1990) (p. 293)

CAS No.: 58-93-5
Chem. Abstr. Name: 2H-1,2,4-Benzothiadiazine-7-sulfonamide, 6-chloro-3,4-dihydro-1,1-dioxide

5. Summary of Data Reported and Evaluation

5.1 Exposure data

Hydrochlorothiazide has been used extensively since 1957 as a diuretic and antihypertensive agent.

5.2 Experimental carcinogenicity data

Hydrochlorothiazide was tested for carcinogenicity by oral administration in one strain of mice and one strain of rats. An increase in the incidence of hepatocellular adenomas was observed in male mice. No increase in the incidence of tumours at any site was observed in two studies in rats.

5.3 Human carcinogenicity data

In one hypothesis-generating study in which many drugs were screened for possible carcinogenicity, associations with hydrochlorothiazide use were observed for cancers of the prostate and of all sites combined, which could have been accounted for by chance.

5.4 Other relevant data

One study provided no evidence that use of hydrochlorothiazide in the first trimester of pregnancy is associated with the induction of birth defects. In rats, no teratogenic, embryotoxic or fetotoxic effect was observed.

Hydrochlorothiazide induced gene mutations in mouse lymphoma cells and sister chromatid exchange in Chinese hamster cells. It did not induce chromosomal aberrations in Chinese hamster cells in vitro or sex-linked recessive lethal mutations in Drosophila. Hydrochlorothiazide induced mitotic recombination and nondisjunction in Aspergillus nidulans. It was not mutagenic to Salmonella typhimurium or Escherichia coli.

5.5 Evaluation

There is inadequate evidence for the carcinogenicity of hydrochlorothiazide in humans.

There is inadequate evidence for the carcinogenicity of hydrochlorothiazide in experimental animals.

Overall evaluation

Hydrochlorothiazide is not classifiable as to its carcinogenicity to humans (Group 3).

For definition of the italicized terms, see Preamble Evaluation.


Last updated: 11 November 1997

    See Also:
       Toxicological Abbreviations
       Hydrochlorothiazide (PIM 265)