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


VOL.: 24 (1980) (p. 85)

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Hydralazine hydrochloride was tested in one experiment in mice by oral administration. A significant increase in the incidence of lung tumours was reported.

Hydralazine is mutagenic for Salmonella typhimurium. Attention is drawn to the absence of published studies on the teratogenicity of this compound.

5.2 Human data

Hydralazine is used in the long-term treatment of essential and early malignant hypertension.

Two studies have suggested an association between hydralazine and human cancer. One was confined to patients with and without hydralazine toxicity, and potential confounding factors were not controlled for. The other involved a small number of subjects exposed to hydralazine, and the possibility of selection bias could not be excluded.

5.3 Evaluation

The experimental data, while providing limited evidence for the carcinogenicity of hydralazine hydrochloride, were difficult to interpret due to certain aspects of experimental design and analysis. The epidemiological data were insufficient. In view of the extensive use of this drug, further studies should be undertaken.

For definition of the italicized terms, see Preamble Evaluation.

Subsequent evaluation: Suppl. 7 (1987)

Last updated: 7 April 1998

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