A South African man who has been in a coma for seven years "awoke" after being given the sleeping pill, Stilnox, which has brought several other patients back from the brink of a death-like stupor.

In 2005, Ayanda Nqinana of Johannesburg was traveling alone along an Eastern Cape road when his car crashed, News 24 reports. The accident left him with severe brain injuries, and doctors said he would probably never recover.

“His eyes, he couldn’t follow any direction. For instance, if you were talking to him, even if you move from this angle to that angle, he doesn’t follow you. He couldn’t talk. Not at all,” Nqinana's wife, Nomfundo, said.

After reading reports of Stilnox's success in the local paper, Nomfundo insisted her husband be given the drug. Less than a week later, Nqinana was awake, able to talk, could recognize family members and remember past conversations.

Stilnox and other sleeping pills with the active ingredient zolpidem have had similar effects in grim cases around the world, including in the United Kingdom and the United States.

It should be noted, however, that Stilnox and other drugs containing zolpidem could have potentially dangerous side effects. All medications should be approved by a doctor.

Discovery of the sleep aid's unintended effects was an accident, however.

In 1994, Louis Vijoen, a 24-year-old switchboard operator from South Africa, was struck by a truck and descended into a deep coma. Five years after the accident, Vijoen's doctor prescribed Stilnox to help help with involuntary spasms. After 25 minutes, Vijoen's mother was astonished to hear her son speak for the first time in years.

Since the drug's effects wear off after about two hours, some patients take multiple doses throughout the day.

Vijoen's doctor Wally Nel, told the Daily Mail he has since prescribed the pill for more than 150 brain-damaged patients and has seen improvements in about 60 percent of them.

But the secret of the pill continues to elude and confuse medical professionals, including those who administer it. Dr. Ralf Clauss, a physician of nuclear medicine at the Medical University of Southern Africa, studied Vijoen's brain after hearing about his story. The results, he said, were simply "unbelievable." However, further research is needed in order to draw any sort of conclusion.

Sally Nielsen is nevertheless one of Nel's converts. Her fiance, Sam Goddard, collapsed on Valentine's Day in 2010, just three months before the two were due to be married. Nielsen fought for the right to administer Stilnox after more traditional rehabilitation treatments slowed, the New Zealand Herald reported. Sure enough, Goddard began to regain the ability to speak soon after taking the drug in 2011 and was eventually allowed to leave the hospital, although his condition requires significant rehabilitative therapies.

According to the Daily Mail, soon after taking the pill, Goddard phoned his parents and said "I'm talking, I'm talking."

In December of 2011, he was taking Ambien four times a day, with the effects lasting for an hour each time. "It is very difficult to comprehend the fact that I can talk now and in an hour or I won’t be able to talk at all," Goddard told MSNBC. "It really sucks."

In a video message that aired on NBC's Rock Center program last December, Goddard thanked his supporters and sounded optimistic about his continued recovery.

Back in South Africa, a homecoming once considered impossible may soon become a reality for Nqinana. Catching up on seven years' worth of missed memories, Nqinana has been holding long conversations with his 9-year-old son, who was only 2 when his father first became unresponsive.

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