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


VOL.: 24 (1980) (p. 243)

CAS No.: 13292-46-1
Chem. Abstr. Name: Rifamycin, 3-{[(4-methyl-1-piperazinyl)imino]methyl}

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Rifampicin has been tested in two strains of mice and in rats by oral administration. It was also tested in mice by subcutaneous administration. After oral administration, it significantly increased the incidence of benign and malignant liver-cell tumours only in female mice of one strain; no evidence of carcinogenicity was observed in animals of the other strain. In rats, no increased tumour incidence was found. The experiment by subcutaneous administration was inadequate.

The available studies on mutagenicity indicated the absence of a mutagenic effect.

Rifampicin is teratogenic for mice and rats.

5.2 Human data

Rifampicin is a commonly used antimycobacterial drug. Its use in human medicine has increased recently.

No case reports or epidemiological studies were available to the Working Group.

In a preliminary report, nine malformations occurred among the children of 229 women exposed to the drug. (Three had defects of the central nervous system, and three had skeletal reduction defects.)

5.3 Evaluation

In view of the limited evidence for the carcinogenicity of rifampicin in mice and the absence of epidemiological studies, no evaluation of the carcinogenicity of rifampicin to humans could be made.

Subsequent evaluation: Suppl. 7 (1987) (p. 71: Group 3)

For definition of terms, see Preamble Evaluation.


Last updated: 7 April 1998

    See Also:
       Toxicological Abbreviations
       Rifampicin (PIM 472)