Methylphenidate (Ritalin) Linked to Chromosomal Changes

The February 28, 2005 Medical News Today reported on a new study that linked methylphenidate, the most widely prescribed of a class of amphetamine-like drugs used to treat ADHD, with chromosome abnormalities, occurrences associated with increased risks of cancer and other adverse health effects. Methylphenidate is the generic name for a group of drugs that includes Ritalin, Concerta, Metadate CD and others.

The article noted that researchers at The University of Texas M.D. Anderson Cancer Center in Houston and the University of Texas Medical Branch at Galveston (UTMB), said they undertook the study because, even though methylphenidate has been approved for human use for more than 50 years, "there are surprisingly few studies" in either animals or human beings "on the potential for serious side effects," such as causing mutations and cancer.

In this Texas study researchers drew blood from children diagnosed with ADHD before they started taking methylphenidate in order to measure the level of chromosomal abnormalities. Then three months after the children had begun taking methylphenidate, the researchers drew the children's blood again and tested it a second time, then compared it to the levels before the drug was taken. All of the children in the admittedly small study showed an increase in chromosomal damage within three weeks.

Lead author Randa A. El-Zein, M.D., Ph.D., an assistant professor of epidemiology at M.D. Anderson who performed the blood studies using several techniques, noted, "A higher frequency of aberrations is reported to be associated with an increased risk of cancer down the line." El-Zein continued, "It was pretty surprising that all of the children taking methylphenidate showed an increase in chromosome abnormalities in a relatively short period of time."