Current treatments for bipolar disorder usually take weeks before they become effective. This creates a problem because when the manic episode begins, if relief doesn’t come from drugs soon enough, the person usually needs to get hospitalized and sedated.

Scientists found that a breast cancer drug tamoxifen was more effective and took much less to work than standard treatments used for this chronic mental state. The reason scientists decided to test this drug was because they knew it targeted the same enzyme called protein kinase C, or PKC, that regulates activities in brain cells as bipolar medications. Both of the drugs lower the activities of this enzyme, the difference is that Tamofixen does it more directly.

In the study, tamofixen was given to eight patients experiencing a manic episode while another eight received a placebo. Three weeks after, 63% of the patients who took tamoxifen had reduced symptoms of mania while the number of those who received placebo and had reduced symptoms was 13 %. Symptoms from the tamoxifen group were reduced and the effects noticed by the fifth day of treatment.

The researchers started patients with 20 milligrams of tamoxifen a day and increased the dosage each day up to 100 milligrams a day. With standard medications, the effects would take three weeks to see results but with tamofixen anti-mania effects were seen at day five.

Researchers are hoping to create a new bipolar drug that would not be tamoxifen itself but the drug that would mimic what tamoxifen does in the brain. Developing such drug would take at least five years before being approved for marketing.