Many shift workers use over-the-counter and prescription drugs to stay awake or fall asleep at the appropriate times – but the evidence behind those practices is weak, researchers say.
No firm conclusions
Use of these drugs for this purpose "has been studied to a very limited extent and the studies that have been published mostly have not been of sufficient quality to allow firm conclusions," said Dr. David Neubauer, associate director of the Johns Hopkins Sleep Disorders Centre in Baltimore, Maryland.
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"Considering the large number of people who do shift work, it certainly is unfortunate that minimal research has been performed to offer clinical guidance to address the problems of inadequate alertness or sleepiness," Neubauer, who was not involved with the new study, told Reuters Health by email.
For the study, Dr. Juha Liira of the Finnish Institute of Occupational Health in Helsinki and colleagues gathered data from 15 trials involving 718 participants. The trials evaluated the effect of melatonin and hypnotic drugs on sleep after the shift, and the effect of modafinil, armodafinil and caffeine plus naps on sleepiness during the shift.
They found that taking a nap and caffeine before a night shift may improve alertness, and daytime melatonin may add around 24 minutes of extra sleep during daylight hours, but the evidence is weak.
For some workers, modafinil improves alertness at work but carries the risk of side effects like headache and nausea, and rarely a serious skin rash syndrome.
More trials needed
In general, the authors cautioned, "The evidence was of low quality and mostly from small trials. Both sleep and alertness promoting agents have potentially serious adverse effects. Therefore, we need more trials to determine the beneficial and harmful effects of these drugs."
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They did not respond to a request by Reuters Health for comment.
Roughly 15 percent of the U.S. workforce usually worked the night shift in 2004, according to a Bureau of Labour Statistics report cited in the review.
For many workers, falling asleep isn't a problem, since they tend to be sleepy getting off the night shift, Neubauer said. The bigger challenge is remaining asleep long enough.
"Anyone with significant problems associated with shift work – whether excessive sleepiness at work or driving home, or with getting sufficient sleep during the hours off work – should confer with his or her primary care provider," Neubauer added. "Some people have much greater difficulty adapting to a shift work schedule and may benefit from behavioural approaches or medications."
Many workers use caffeine to stay awake at night, and fewer use prescription medications, but they can have a place for some patients, he said.
Caffeine and melatonin can be purchased over the counter in various formulations. Modafinil (Provigil) and armodafinil (Nuvigil) require a prescription.
Policies and systems to reduce fatigue
Claire C. Caruso told Reuters Health by email that shift work, and long work hours, can put workers' health and safety at risk "by disturbing sleep and circadian rhythms and reducing time for family and non-work responsibilities."
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Caruso, who was not a part of the new review, is a research health scientist at the National Institute for Occupational Safety and Health in Cincinnati.
There are non-pharmacologic ways to reduce the strain of shift work, she said.
Aside from improving work schedules to allow for more time for sleep, managers can institute policies and systems in the workplace to reduce fatigue, she said.
Also, workers can try to allow enough time for getting to sleep and use good sleep practices, like keeping the bedroom dark, maintain a bedtime routine and avoiding screens for an hour before sleep.
Workers can also educate the important people in their lives about their special needs to reduce conflicting demands from work and home life, Caruso said.
"Stimulants and sleep medications can have side effects, can become addictive, and generally have been tested for short-term use," she said. "In addition, they do not completely remedy the effects of inadequate sleep, and questions remain about their long-term use."
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