New Scientist, October 2002
Alertness pill seeks wider uses
A drug designed to help people with a particular sleep disorder to stay
awake could soon be licensed to perk up sleepy shift workers and others
affected by drowsiness. The prospect is stirring up a debate about the
dangers of popping a pill to counter a sleep-deprived lifestyle.
Provigil, as the drug is known in the US and Britain, is approved for
treating the daytime sleepiness associated with the rare condition called
narcolepsy, which makes people fall asleep involuntarily. But last week,
the drug's manufacturer, Cephalon of West Chester, Pennsylvania, announced
results from a clinical trial of 209 shift workers that showed it helps
those with "shift work sleep disorder" - excessive sleepiness
caused by odd working hours.
The trial is part of Cephalon's attempt to expand the range of conditions
Provigil can be used for. Ultimately, the company hopes it can be prescribed
to treat sleepiness that results from any medical condition, and plans
to submit data from this and other trials for approval for such use to
the US Food and Drug Administration (FDA) this year.
But critics fear that this could lead to the use of Provigil being extended
from those with sleep disorders to healthy people who are simply sleep-deprived.
24/7 generation
While experts differ as to whether shift work sleep disorder is a real
medical condition, it is clearly caused by lifestyle. Police, hospital
staff, pilots and people who work at all-night stores are among the countless
groups of workers likely to be affected. Get the drug approved to treat
such people and the decision whether to treat those who are simply working
or playing too hard becomes a distinctly grey area.
Some fear there would then be little to stop Provigil becoming the elixir
of choice for the 24/7 generation. Several sleep researchers told New
Scientist that patients with demanding careers and lifestyles are beginning
to ask for Provigil to help them stay alert as they burn the midnight
oil.
"It's happening already," says Thomas Scammell, a sleep expert
at the Beth Israel Deaconess sleep disorders clinic in Boston.
The clinical trial on shift workers is the latest of a string of studies
showing how Provigil could benefit different groups of people. One study
of military helicopter pilots showed that the drug helped them stay alert
and capable of performing complex tasks for almost two days without sleep.
Other studies have shown the drug seems to help patients with multiple
sclerosis cope with fatigue. Ongoing trials are now looking at the drug's
effect on tired truck drivers, medical staff and soldiers.
Wakeful not 'wired'
That the drug works so well is no surprise, as previous studies have
shown it to be a potent stimulant. How it produces prolonged alertness
is not well understood, but it is thought to act specifically in the brain's
pre-frontal cortex. This is one of the most active areas of the brain
in people who are awake, governing planning, memory and what we pay attention
to.
The drug's localised effect may explain why it increases wakefulness
without triggering the "wired" feeling of stimulants such as
coffee and amphetamines. Surprisingly, tests also found that when the
drug wore off, there was no noticeable need for an extended sleep to recover.
Critics of more widespread use of Provigil fear that the drug might give
people a false sense that they can cheat their need for sleep, while in
reality they may be accumulating a sleep debt that will ultimately harm
them.
Sleep deprivation leads to cognitive impairment, as well as seriously
disrupting the immune and hormone systems, although it is not known how
long these effects last. And Paul Blake of Cephalon acknowledges Provigil's
limitations: "The drug isn't a replacement for sleep," he says.
On the other hand, Provigil could help prevent accidents common among
shift workers, and make a big difference to soldiers on sustained operations
or rescue workers at a major emergency.
"It's an interesting challenge for society and for the FDA,"
says Neil B. Kavey, director of the Sleep Disorders Center at Columbia-Presbyterian
Medical Center in New York. "We have to make sure nobody's going
to get hurt," he says.
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