This is the first in a six-part series that explores challenges people face when they seek treatment for mental health issues. The final two articles in the series will explore reasons for problems with care and how to help yourself and loved ones to get care that works.

Rebecca's day was not going well. She was responsible for a large chunk of financial affairs for a mid-sized multinational corporation. She was expected to deliver a high rate of return on investments -- while the market was tanking. On top of that, some of the company's divisions had financial officers who didn't seem to understand their jobs.

In addition, her boss wanted her to "take a more optimistic view" of some of the overdue balances from customers. Doing so, she was certain, would put them on the wrong side of any future audit or investigation.

By the end of the day, Rebecca once again felt defeated. "I'm not just running in place," she thought, "I'm losing ground every day."

The next morning, the whole office was shocked to hear that Kevin -- the best of her employees by far -- had died of an aneurysm in the airport as he headed home from a business trip she'd sent him on. He was 32 years old, and left a wife, a 2-year-old daughter and a newborn son.

For Rebecca, it was the last straw. Before long, she found herself in a psychiatrist's office, diagnosed with depression.

The doctor prescribed two drugs, one for depression and one for insomnia. Despite the fact that the sleep aid made her very groggy, he increased the dose by 50 percent less than a week later, and doubled the dose of the antidepressant.

A week after that, Rebecca reported extreme nausea and faintness, and the doctor temporarily dropped the dose of the antidepressant, then raised it so that it was triple the dose she had started with. He recommended stomach remedies for the nausea.

Rebecca mentioned that she had a new symptom, low-grade mental confusion: which soap in the shower is mine? What do I normally eat for breakfast? She also reported that she now had a slight tremor and found her employees eyeing her with concern.

After six weeks of treatment, Rebecca was leaving work to go home in the middle of the day. She slept 18 hours a day and was very groggy the rest of the time. The doctor stopped prescribing the sleep aid, and upped the dose of the antidepressant to four times the starting level.

A couple of weeks later, he switched Rebecca to a different antidepressant, and then doubled the dose. She continued to deteriorate. She made notes of comments from her subordinates: "You're not yourself. You seem stressed out and very distant," and "It's like you're not present. You don't seem at all engaged."

A colleague commented, "You seem very shaky, on edge, and stressed out."

Her husband said, "The only thing I see happening with this medicine is that you're less engaged with everything. You don't seem engaged with your work at all -- you aren't even rollerblading, which was one of the few things you liked doing. You're more withdrawn, unhappier, more tired, less forthcoming."

One day when they were in the grocery store, Rebecca's husband stacked some grapefruit in the child seat of the shopping cart. A moment later, he was looking at some produce when he heard a "splat" sound. He picked up a grapefruit from the floor and glanced curiously at Rebecca, since she was the one standing at the cart.

"Did you see that it was about to fall?" he asked.

"Yes," she said.

"Did you try to catch it?"

"No."

He started laughing, and said, "Boy, you really need to get off that medicine!"

That same week, Rebecca was disconcerted to find that random parts of her body had started to jerk unpredictably. She also found thoughts of suicide filling her head, taking up all the space with vivid and graphic images of various ways she could kill herself.  With the last bit of fortitude she had, she called the doctor.  It was now three months into treatment, and he switched her to a third antidepressant.  This one seemed to work - or at least it didn't create new problems that were worse than the ones she had started out with.

Years later, Rebecca reflected, "Finding the right drug was a brutal process. Of course, you are depressed when you start treatment, so every action you have to take feels like climbing a mountain with weights on your back. If I hadn't been obsessive about writing everything down, I could have committed suicide as a result of the second antidepressant, not realizing that all the suicidal thoughts were a side effect of the drug."

She continued, "I almost lost my job during the three months when I was being treated with several drugs that only made things worse. Before I started treatment, no one seemed to know that I was depressed. After I started treatment, everybody at work thought that something was seriously, seriously wrong with me. A few people even thought that I was dying. And I couldn't get any work done. I couldn't follow a train of thought, couldn't make decisions -- it was much worse than before I started treatment."

Rebecca's experience is not unusual.

An article by David H. Freedman in The Atlantic magazine reports, "A number of studies have indicated. . .that most antidepressants don't do better than placebos, but patients filled more than 250 million prescriptions for them in 2010. The vast majority of drugs don't work in as many as 70 percent of patients, according to an estimate from within the pharmaceutical industry."

And side effects are very common.

Dr. David M. Reiss, a psychiatrist in private practice in San Diego, offered a different slant on the question about whether the benefits of these drugs outweigh the downsides. "The problem is that antidepressant medications are prescribed prematurely, often when not really necessary, and very often at too-high dosages. That causes more side effects and problems than usefulness."

He gave an example of the mixed results patients experience. One class of antidepressants "will decrease anxiety about 40 percent of the time, be neutral regarding anxiety 40 percent of the time and increase anxiety 20 percent of the time."

He pointed out, though, that when antidepressants "are truly necessary and carefully monitored. . .then the medications do serve a useful purpose almost all of the time."

It may be very hard for a patient to know how to deal with the trial-and-error approach to drug dosing. Two action steps that helped Rebecca were keeping written records of her symptoms and having a family member watch for changes in her behavior. Both of these provided data which, eventually, led the doctor to a drug that helped her.