US warns two drugs may have sexual side effects
Two Merck drugs for treating male baldness and enlarged prostate
will now carry extended labels
to add more possible sexual side
effects, US regulators said.
The changes involve Propecia and Proscar, both of which contain the active ingredient
finasteride, after patients reported additional adverse effects that
were not apparent at the time of the drugs' approval, the US Food and Drug Administration
said Friday.
The new Propecia label will include "libido disorders, ejaculation
disorders, and orgasm disorders that continued after discontinuation of the drug,"
the FDA said.
Propecia is a drug to treat male baldness.
Proscar, which treats symptoms of
enlarged prostate, will now have a label that adds "decreased libido that
continued after discontinuation of the drug."
In addition, both labels are being revised to "include a description of
reports of male infertility and/or poor semen quality that normalized or
improved after drug discontinuation," the FDA said.
FDA spokeswoman Stephanie Yao said the drugs were previously known to cause
adverse sexual events in a small number of patients, and that information was
included on labels at the time of approval.
The latest labeling change "expands
the list of sexual adverse
events reported to the FDA postmarketing," she told AFP,
adding that "no new clinical studies were reviewed to evaluate these
adverse events."
Proscar was approved for the US market in 1992 and Propecia in 1997. In
2011, both drugs' labels were "revised to include erectile dysfunction
that continued after drug discontinuation," the FDA said.
Last year, labels for Proscar and Propecia were also changed to advise of
the possibility of an increased risk of high-grade prostate cancer.
The agency noted that even though "clear causal links between
finasteride (Propecia and Proscar) and sexual adverse events have NOT been
established, the cases suggest a broader range of adverse effects than
previously reported in patients taking these drugs."
Since these side effects may be important to some patients, doctors were
urged to discuss them with patients when deciding on treatment options.
In the case of Propecia, clinical trials showed 3.8 percent of men had
reported one or more adverse sexual experiences, compared to 2.1 percent who
were taking a placebo.
"Propecia and Proscar are generally
well tolerated and effective for their respective intended uses in accordance
with their approved product labeling," Merck said in a statement.
The company added that "a causal
relationship between the use of Propecia or Proscar and continued sexual dysfunction
after discontinuation of treatment has not been established," and
expressed support for ongoing monitoring of adverse event reports
沒有留言:
張貼留言