Many of the drugs are labeled "non-habit forming." But as the experts at Consumer Reports found out, some still carry a risk of dependency and can cause serious side effects.
Tara Matthews has had chronic insomnia on and off for years. She relied on over-the-counter sleep aids to help her fall asleep.
"When I can't fall asleep it makes me very anxious because I know how much I have to do the next day," Matthews said.
What she didn't know is that over-the-counter sleep aids typically contain diphenhydramine and doxylamine - antihistamines that can make you sleepy.
"Although these ingredients are not physically addictive, there could be a risk of psychological dependency," said Lisa Gill with Consumer Reports.
A national survey by the consumer organization found that 20 percent of respondents had taken over-the-counter sleep medication within the past year. And in that group almost 1 in 5 took them on a daily basis. Most concerning - 41 percent said they took them
for more than a year.
At the time of their approval as over-the-counter sleep aids, there was not enough evidence to show that the drugs caused dependence, so the label "non-habit forming" still remains.
The FDA tells Consumer Reports using a sleep aid for 2 weeks or less at the labeled dose makes it "...very unlikely that the consumer will become dependent on it."
But Matthews says she's not convinced.
"Maybe I would have looked for alternatives sooner," she said.
Label warnings on over-the-counter sleep aids also say they can cause serious side effects like next-day drowsiness and confusion. And studies show frequent use can increase the risk of dementia and even Alzheimer's disease.
If your insomnia is persistent, it's time to see your doctor.