(Ivanhoe Newswire) -- A drug more commonly associated
with breast cancer treatment is holding out new promise for people suffering
through the manic phase of bipolar disorder.
Researchers report tamoxifen (Nolvadex) effectively targets a key protein in the
brain thought to go into overdrive when bipolar disorder turns from depression
into mania. In a study involving 16 patients who received either tamoxifen or a
placebo, 63 percent in the active treatment group saw a relief of their symptoms
by the end of three weeks versus just 13 percent on the sham pill.
Tamoxifen also went to work quickly, with people on the drug showing signs of
improvement by the fifth day of treatment. Current drugs used to treat bipolar
mania usually take weeks to go into effect. Tamoxifen gets the job done sooner,
report the investigators, because it directly inhibits a protein, known as
protein kinase C, or PKC. Other drugs take a more roundabout approach.
So, will tamoxifen become the standard of care for people with bipolar disorder?
The authors stop short of that conclusion, noting the drug blocks estrogen
(which is why it's used for breast cancer) and also raises the risk for
endometrial cancer.
But the results seen in this study are expected to open the door to other new
treatments that may be able to duplicate tamoxifen's effects in the brain
without causing those side effects. "Large controlled studies with selective PKC
inhibitors in acute bipolar mania are warranted," write the study authors.
Bipolar disorder affects nearly six million Americans, who suffer through severe
mood swings ranging from the depths of depression to periods of mania in which
they are prone to potentially harmful behaviors that can reel out of control and
even end in hospitalization.
SOURCE: Bipolar Disorders, published online Sept. 12, 2007
