Jenna woke up on her kitchen floor. Dimly, the California teacher remembered bending over the sink, trying to swallow water. According to the clock, that had been more than an hour ago. She fumbled for her phone but couldn't think clearly enough to text for help.

"I felt these horrible jolts running through my head and body; I couldn't stop jerking," she recalled. "Then I began seeing stuff that wasn't there, creepy-crawly things. I didn't know what was happening, but I worried I might be dying."

The previous morning Jenna, then 33, had inexplicably woken up shaking.

"I'm usually pretty confident and outgoing, but I felt like I couldn't leave my apartment," she said. "Somehow I made it to school. My boss noticed the shaking and was concerned; I told him I wasn't sure what it was and I went home early."

There, things got worse. Her twitching intensified, and she grew increasingly confused. Then she passed out.

Once Jenna regained consciousness, she hauled herself to her sofa. Over the next two days she couldn't eat or drink, and her mind drifted in and out. Finally, Jenna's mother stopped by—and found her daughter curled up in a fetal position on the floor, clutching her cell phone, twitching uncontrollably.

"My mom dragged me to the car and got me to the emergency room," Jenna said. "The ER staff asked if I'd taken any drugs or alcohol, and I told them I hadn't."

When a nurse wanted to know what prescriptions she was on, Jenna told them generic Xanax, noting that two nights before she passed out, she'd run out of the pills she'd been using for anxiety.

After testing her blood and urine, staffers administered another drug that, like Xanax, is in the benzodiazepine family.

"Almost immediately, I stopped shaking and felt totally normal," Jenna said. "It was as though nothing had ever happened. Nobody there told me, but I put it together: I'd been in withdrawal. I was dependent on Xanax."

Jenna had first gotten a prescription eight years earlier when she was a student and saw a doctor, complaining of insomnia. After discussing her problem, "he decided I was anxious," she said. "I had a busier life than some, but I didn't think I was especially anxious. He told me there was this great drug I could take. He prescribed a milligram per day of the generic form."

At first, she loved it.

"It was amazing," she said. "I could sleep anywhere, on the spot."

A few months later, though, her insomnia returned, along with a new sense of nervousness that struck between pills. Over the next couple of years, her doctor upped the dosage until it reached 6 mg per day, an unusually high level.

Jenna's experience—extreme as it is—shows that this drug, which more and more women today are using, may carry severe risks.

"Dependence on benzodiazepines like Xanax is a serious problem, especially among young women," said Harris Stratyner, cochairman of the medical scientific subcommittee of the nonprofit group National Council on Alcoholism and Drug Dependence. "Frequently, it's not because they've been abusing the drugs; it can be caused by following the prescription their doctor gave them."

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A tranquilizer, Xanax has many close cousins, including familiar names Valium, Klonopin and Ativan. Alprazolam (Xanax's generic form) is the most prescribed psychiatric drug in the United States, reports health care technology and information company IMS Health. There's good reason: Used properly and under the right circumstances, Xanax works fast and safely to relieve symptoms of anxiety and panic disorders, as both clinical studies and patient experience show.

Benzos activate the brain's GABA receptors, inhibiting neuron activity and leaving you more relaxed and often sleepier.

"With Xanax, you typically feel the effects within 15 to 20 minutes of taking it, and they wear off within six hours," said Jennifer A. Reinhold, assistant professor of clinical pharmacy at the Philadelphia College of Pharmacy. "In contrast, with SSRI [selective serotonin reuptake inhibitor]antidepressants—which are also prescribed for anxiety disorders—patients generally experience a lag time of four to six weeks before they start working."

Doctors also often prescribe Xanax as a short-term fix for moments of acute anxiety or to help manage specific phobias.

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"I'm not a fan of Xanax, but I might prescribe just a few pills on occasion for patients with fear of flying; it works," said Dr. Catherine Birndorf, a New York City psychiatrist and a self contributing expert.

Yet its cred as a highly effective drug also makes it a frequently abused one: Experts say that benzos are so widely available and sometimes used so casually that they can seem benign.

"The culture in which we live sends messages that there is no reason to tolerate discomfort," said Susan Foster, vice president and director of policy research and analysis at the substance use and addiction nonprofit CASAColumbia, adding, "That fuels misuse of prescription medications."

Consumed daily in high doses, even for a month, Xanax can lead to physical dependence. But just accepting pills (hashtag: #Xannies) from friends here and there is risky—and not only because it's against the law. It puts users at risk for a psychological dependence, in which they believe they can't get through life without help from a pill.

"I know from a clinic where I work that even people who aren't physically dependent on benzos can get desperate for them," Reinhold said.

The more people regularly take these little pills to soothe themselves, the more their minds may start to crave them.

As she notes: "Maybe they can't get through a job interview or a big date unless they have one. They ask friends for them, they go to multiple doctors or they may even try online pharmacies that illegally hand out pills without prescriptions."

An estimated 14.7 percent of Americans ages 21 to 34 have taken tranquilizers without a prescription or even recreationally, according to 2012 data from the Substance Abuse and Mental Health Services Administration. Meanwhile, the number of ER visits from people misusing or abusing alprazolam skyrocketed 172 percent from 2004 to 2011, the most recent federal statistics available.

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The drug can be particularly dangerous when taken in combination with other substances.

"If you mix a benzo with another drug that subdues your nervous system—painkillers, alcohol, antihistamines—the effects can be dangerous or deadly," Reinhold said. "Remember Heath Ledger?"

Even when used as prescribed, Xanax can become habit-forming, Birndorf said.

"As your body acclimates to it, you could end up needing more of it, and sooner, to get the same response."

If that happens and you abruptly stop taking the drug, you might go into withdrawal. This can lead to muscle twitches, depression, anxiety and, in its severest form, seizures. Says Dr. Stuart Gitlow, an addiction psychiatrist and president of the American Society of Addiction Medicine, "Withdrawal from benzos can be more dangerous than withdrawal from heroin."

Those risks are very real for women; an estimated 32.5 million alprazolam prescriptions were written for women in 2012 versus 15.3 million for men, according to IMS Health.

"Women now are more aware of just how bad stress is for them, and they are more likely to seek out remedies," Birndorf said. "They may believe that taking Xanax to relieve those feelings is beneficial. But it doesn't address whatever was causing their stress to begin with."

Still, the fact is that some doctors—who more than anyone should be aware of the risks—are doling out Xanax in irresponsible and harmful ways. Though Xanax's prescribing information has long included clear wording about potential dangers and warnings against overprescribing, and medical organizations such as the American Psychiatric Association echo these in their guidelines, some doctors aren't paying attention.

Benzos are now so mainstream that "psychiatric issues are sometimes being treated by primary-care physicians, who may not have enough training in or understanding of these drugs," Gitlow said.

More than half of all benzo prescriptions are written by primary-care physicians, not psychiatrists, according to one study published in the journal Psychiatry.

"Doctors who don't understand these drugs often up the dosage—to treat symptoms that the drug itself may be causing," he added.

The lack of awareness is complicated by the fact that many patients self-diagnose and ask for the drugs by name.

"It's not that there are a lot of doctors just saying, 'Oh, I'll hand this stuff out like gummi bears,'" Gitlow said. "But people are in distress, and they want an instant cure—so it's hard for some physicians to withhold it, especially when they know they'll just get it elsewhere."

Even psychiatrists can feel trapped by a system that pushes them to opt for a quick fix rather than a long-term solution.

"Physicians have less and less time to spend with patients or may see them only occasionally, when their talk therapist sends them in for drugs," noted Dr. Harold J. Bursztajn, a forensic psychiatrist and an associate clinical professor of psychiatry at Harvard Medical School.

"Anxiety can almost always be treated in other ways, but too many doctors are too rushed to search for the root of a patient's problem when there's a supposed solution that seems quick, easy and effective."

Once a doctor prescribes the drug, follow-up care may be lacking, as Kim in Pennsylvania discovered. The energetic then-20-year-old college student started having frequent anxiety attacks and visited a doctor, who had previously prescribed generic Xanax for her to use as needed for occasional anxiety. This time, he put her on it daily.

The drug soothed her panic but made her so drowsy that she began to oversleep and miss classes. Her GPA dropped, and she took to avoiding her friends. After a month, the anxiety returned in between doses.

"I was taking it religiously, but the feelings were three times as strong," she said.

The next semester, she took a medical leave of absence from school and holed up in her room at her parents' house.

Kim discussed her situation with the doctor. He suggested increasing the dosage, but she refused. She'd become concerned about her reaction to the drug.

"Between doses, it felt like my spine was hooked up to an electrical socket and there was a chemical storm inside my head," she said.

The symptoms were worst when she woke up: "I had to keep my pills beside my bed so that before I even opened my eyes, I'd be melting one under my tongue. I'd dry heave and cry until it kicked in."

Then one morning, she experienced what's known as a paradoxical adverse reaction—a rare, unexpected response to a drug that can't be explained. She had popped her pill and was lying there waiting for it to take hold, except nothing happened. She felt so scared and shaky that she took another. And then, in a half hour, one more—followed by a fourth one 30 minutes later. Within minutes of downing the last pill, her legs began shaking violently. The toes on her left foot curled up, and her tongue stiffened.

"The next thing I remember is the paramedics running in," she said. "I'd had a seizure."

The debilitating pangs of interdose withdrawal had been awful enough. Now, Kim started to worry about how she would ever get off the drug.

What makes it even rougher for women who become dependent on benzos is that many physicians do not fully understand how to wean them off the medication.

"While most doctors should know how to taper properly, not everyone does," Birndorf said.

Few women are more aware of that than Emily, who lives in Indiana. She was prescribed generic Xanax at age 25, a few months after she'd had a baby. She was filled with anxiety, often irrational.

"I worried that someone would feed her something she might choke on," she recalled.

When the drug didn't help and she became desperate, she admitted herself to a psychiatric ward; during the week she was there, relatives cared for her little girl.

Emily was taken off alprazolam and put on the generic form of Klonopin, which is slower-acting. After being released, she followed up with her doctor, who continued her on that drug, but Emily didn't feel much better on it. Her anxiety attacks persisted.

"Every day was a struggle," she said.

After several months, she started looking for other doctors to get her off the pills. One wanted her to go cold turkey, but she'd been reading up online and knew the dangers of benzo withdrawal.

"Once you've been on Xanax or similar drugs for a month or more, you may need to taper off them gradually," Birndorf explained.

Tapering is a stepladder approach that involves slowly decreasing your dose by tiny increments. It may also include switching from a faster-acting benzo like Xanax to a slower one, such as Klonopin, as the hospital had Emily do.

"If you've been on a high dose for years, tapering from benzos can possibly take much longer than with other drugs, like SSRIs—maybe even a full year," Birndorf said.

Sometimes, she points out, patients don't comply with the tapering process because they don't realize how dependent on the medication they may have become.

Unfortunately, relatively little is being done in this country to increase awareness of benzo pitfalls—and for now, too many women are learning the hard way. Although the Centers for Disease Control and Prevention supports more education of health care professionals about benzo misuse, along with increased monitoring of prescription drugs such as these, for the most part, painkillers get more attention in the medical community.

After contacting doctor after doctor, last year Emily found a nurse-practitioner knowledgeable about benzo tapering who helped her cross over to generic Valium. She's still going through the process, with bouts of anxiety when she cuts a dose.

"But at least now I know why," she said. "And I'm getting better." She hopes to be off benzos altogether within the year.

Now living with her fiancé, Kim is also working with a nurse-practitioner to taper off benzos. She has reenrolled in school but at times still struggles to get by.

"My body and my brain have to learn how to handle even the most minor stresses on their own all over again, like driving on busy roads," she said.

So far, Jenna is the only one of the women in these cases who has made it completely off benzos. About a year after her trip to the ER, she married and discovered that she was pregnant. She'd been trying to taper on her own, but knowing that the drug could potentially hurt the fetus, she managed to find a benzo specialist a three hours' drive away. Because of her pregnancy, she chose to taper faster than usually recommended.

"I had some withdrawal symptoms—shakiness and feeling scared all the time," she said. "But it was a compromise I had to make for the sake of my baby." She had a healthy girl.

Jenna has cofounded an online support group; it now has more than 500 members. "What I hate is how Xanax has become known as such a cool pill," she says.

"You watch a sitcom and someone says, 'Oh, I can't get to sleep without white wine and a Xanax!' and all I can think is, Wow, that's not funny after you've lived through it."

This article originally appeared on Self.com.