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


VOL.: 24 (1980) (p. 211)

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Reserpine was tested in two experiments in mice by oral administration; in one experiment it induced malignant mammary tumours in females and carcinomas of the seminal vesicles in males. It was tested in three experiments in rats by oral administration; in one experiment it increased the incidence of pheochromocytomas in males. The other study in mice and the other two studies in rats were inadequate for evaluation.

Reserpine is embryotoxic and has effects on reproduction. There is limited evidence that it is teratogenic in experimental animals. It was not mutagenic in Salmonella typhimurium.

5.2 Human data

Reserpine is used mainly for the treatment of mild or moderate hypertension.

Thirteen case-control and two cohort studies on the relationship of reserpine to breast cancer were available to the Working Group. Between and within studies, estimates of relative risk for different measures of reserpine use varied from as low as 0.6 to over 3. Many of the positive findings were not coherent with one another; and the studies considered to be the most satisfactory, methodologically, showed little or no evidence of an increased risk.

Two studies of pregnant women receiving reserpine failed to find clear evidence of teratogenicity.

5.3 Evaluation

There is limited evidence that reserpine is carcinogenic in experimental animals.

The studies in humans are not consistent in showing an increase in risk of breast cancer associated with reserpine use; and, considering all studies together and the methodological problems of some, such an increase appears unlikely. Because of sampling variation, however, a small increase in risk (of the order of 50% or less) cannot be ruled out.

For definition of the italicized terms, see Preamble Evaluation.

Previous evaluation: Vol. 10 (1976)

Subsequent evaluation: Suppl. 7 (1987)

Last updated: 7 April 1998

    See Also:
       Toxicological Abbreviations
       Reserpine (PIM 467)
       Reserpine  (IARC Summary & Evaluation, Supplement7, 1987)
       Reserpine (IARC Summary & Evaluation, Volume 10, 1976)