Schizophrenia Drugs May Up Tumor Risk
A statistical "signal" links Risperdal and other schizophrenia drugs to pituitary tumors, FDA researchers report.
WebMD News Archive
May 31, 2006 – A statistical "signal" links Risperdal and other
drugs to pituitary tumors, FDA researchers report.
The finding is not proof that these extremely useful drugs cause these
benign (noncancerous) tumors. And it does not tell how often patients develop
drug-linked pituitary tumors, says Duke University psychiatrist P. Murali
Doraiswamy, MD. Doraiswamy was a member of the research team led by the FDA's
Ana Szarfman, MD.
The researchers used a highly sophisticated computer program to analyze the
FDA's database of 40 million combinations of drugs and side effects reported by
doctors and patients. They found 77 reports of pituitary tumors in patients
using seven different antipsychotic drugs. Seventy percent of these reports
were in patients taking Risperdal.
"When you put all the data together, you get a strong biochemical
plausibility that this is a Risperdal effect," Doraiswamy tells WebMD.
"But we cannot rule out the possibility it is a spurious association. No
one should stop Risperdal because of this. Even if Risperdal is linked to
pituitary tumors, it may turn out to be fairly rare."
Szarfman, Doraiswamy, and colleagues report the findings in the June 2 issue
of the journal Pharmacotherapy.
Small Risk, Benign Tumors
The tumors linked to Risperdal and other drugs are not necessarily
dangerous. Many are microscopic. Few are larger than 1 millimeter.
"These are benign tumors, better thought of as a cyst," Doraiswamy
says. "They grow slowly and, generally, locally. Most are very tiny. But
sometimes they grow, and when they do, they press on surrounding tissue and
cause hormonal problems. Or they can press on the optic nerve and cause some
loss of vision."
Janssen, the Johnson & Johnson subsidiary that makes Risperdal, is
already telling patients about animal studies and human case reports that link
antipsychotic drugs to pituitary tumors, or, as doctors call them,
"Last year, we updated our labeling to ensure that health care
professionals are aware of reports of benign pituitary adenomas in patients
using antipsychotic medications," Janssen spokeswoman Theresa Gaines tells
WebMD. "Benign pituitary adenomas are present in 10% to 25% of the general