Controversial findings were recently published in the journal Neurorehabilitation suggesting that the insomnia drug zolpidem roused three severely brain-injured patients from the coma-like persistent vegetative state (PVS).
Zolpidem is better known by its trade name Ambien, and has also been in the news recently for causing unusual sleep behaviour such as sleep-driving.
The study published by Drs Ralf Clauss and Wally Nel reported on three patients diagnosed as being in PVS. All three were temporarily but reliably roused after being given the drug each morning over a period of 3 to 6 years.
It has been suggested, however, that the patients may not have genuinely been in PVS, as this state is thought to be misdiagnosed in up to 40% of cases.
Even if these patients were misdiagnosed, the results would still be interesting for those hoping to find an effective treatment for people who have chronic problems with arousal after brain-injury.
Furthermore, the fact that the treatment was consistent over such a long period is promising. Nevertheless, the drug will need to be tested in comprehensive clinical trials to show that the treatment is widely beneficial and the improvement in these patients was not due to person-specific factors.