"One has to be cautious, though, because depression waxes and wanes on its own, and it's always hard when looking at a small number of people, whether it is the effect of the drug, or if it would go away anyway," said Robbins. "We have to make sure we are careful with the studies. There is a long history of people making claims about substances helping depression."
But, he warns, taking a drug for an off-label use can be dangerous -- and not only for Cheryl's health.
"I have delayed telling my story for so many years, and the main reason is because I am risking my ability to get this drug for my own well-being," she said. "It's a federal offense. RU-486 is a schedule 1 drug, the most controlled we have."
Cheryl, who is uninsurable except in an expensive high-risk pool, said she averages about $15,000 to $20,000 a year on her drugs. Her lucrative high-tech job allows her to medicate herself.
"I am absolutely clear it saves my life and my ability to think, and to be productive," said Cheryl. "I have to make a living as a business consultant and work for my clients and function, and this is the only way I am able to do that. Without it, I wouldn't be here."
In major depression with psychotic features, a person experiences depression along with a detachment from reality, as well as delusions and hallucinations, according to the National Institutes of Health.
A family history of the illness increases risk. Cheryl learned later that both her mother and grandmother had suffered from the same problem illness.
Some hear voices telling them they are evil or they don't deserve to live; others may think their body is filled with cancer and "rotting inside," according to NIH. The risk for suicide is five times that of other forms of depression.
Depression affects about six to seven percent of the population at any given time, according to Robbins. About one to two percent have psychotic symptoms.
"It's a very scary illness," said Robbins.
"Clearly there is some genetic loading," he said. "But in the early course of depression, the first, second or third episode has a precipitant - a physiological or psychological stressor. After you've failed an exam or you think you are going to lose your job - life's stressors are triggers. And it's very common after having a baby."
"Usually the psychotic symptoms thematically associated with depression are very negative. Delusional guilt that things are their fault," said Robbins. "Delusions can also be very scary on the person affected. They hold a false belief, and to reason with them is not helpful."
Doctors treat psychotic depression with antidepressants and antipsychotic drugs, which help to treat the mood and the psychosis. Talk and behavioral therapy are ineffective.
"As is the problem with many mental illnesses, we don't know what the trigger is for depression," he said. "We know there are changes in neurotransmitters, and the treatment is altering them, but we have not had as much success as we would like."
As a last resort, patients may undergo electroconvulsive therapy (ECT).
About 80 to 90 percent get better with ECT, a procedure that is now much "slicker," according to Robbins.
"There is an anesthesiologist who puts you to sleep, and your muscles are paralyzed so you are not flailing around like in a real seizure," he said. "It's not like going back to watching, 'One Flew Over the Cuckoo's Nest,' and you're awake and it's a horrible experience."