Scientists from Bath University, with the University of Texas in Austin, reveal in the journal, Neuropsychopharmacology that experiments conducted on mice show that Accutane makes the rodents behave in ways recognized as depression.
Isotretinoin is a synthetic retinoid used as an oral treatment for severe nodular acne that has been linked with depression and suicide in patients. Isotretinoin is also sold under the brand names of Accutane, Roaccutane, Amnesteem, Claravis and Sotret.
The purpose of the Neuropsychopharmacology study was to test the theory that chronic administration of Accutane could lead to depression related behaviors in mice.
"You can't ask a mouse if it is depressed," researcher Sarah Bailey, of the University of Bath, said. "So we used two tests to model behaviour."
Both tests involved putting the mice under stress. In one test, the mice were suspended by their tails and in the other, they were put in water and forced to swim. Under these circumstances, the study author's note, normal mice will swim, climb or thrash around in attempt to escape, in between periods of immobility when they appear to be resigned.
For years, Roche has denied that Accutane causes depression and suicide and internal FDA documents show the agency was aware of these risks almost since the drug came on the market.
In 1985, Accutane's package insert for physicians first mentioned reports of depression in patients being treated with Accutane. In 1986, the physicians were again notified that Accutane users who became depressed saw their depression go away when they discontinued the use of Accutane but that the depression came back if patients went back on the medication. Doctors were also informed that simply removing the patient from Accutane treatment may not be sufficient to treat the depression and that a follow up for depression may be necessary.
Jumping ahead to a decade later, a 1998 FDA memo states that: "Given all the pieces of evidence available, it is difficult to avoid the conclusion that Accutane can adversely affect the adult human brain in clinically significant ways and that Accutane use is associated with severe psychiatric disease in some patients."
The FDA memo recommends "active consideration of removal of Accutane from the market." The recommendation was ignored.
In April 1998, the FDA instructed Roche to strengthen the warnings on Accutane and alert doctors to the risks of "depression, psychosis and, rarely, suicidal ideation, suicide attempts and suicide."
The FDA stated that, "This claim is particularly troublesome in light of information recently presented in a Dear Doctor letter that Accutane may cause depression, psychosis, and rarely, suicidal ideation, suicide attempts and suicide."
In conclusion, the FDA ordered Roche to "prominently disclose information about the psychiatric disorders described in the warnings section of the revised labeling" in Accutane ads.