International Agency for Research on Cancer (IARC) - Summaries & Evaluations
HYDRALAZINE AND HYDRALAZINE HYDROCHLORIDE
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
5.2 Human data
Hydralazine is used in the long-term treatment of essential and early
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
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