PONTE VEDRA, Fla. (Ivanhoe Newswire) -- It's more common than you might think. More than 20 percent of prescriptions are written for conditions they're not approved for, and in a recent study, one-third of patients with metastatic breast cancer had received drugs off-label. The choice is your doctor's, but should you take it into your own hands?

When attorney Allison Keller learned she had multiple sclerosis a year ago, she armed herself for the battle ahead.

"I read The New England Journal of Medicine, obviously highly-respected, and read that it basically had a 70-percent better rate than the top medicine out there," Keller told Ivanhoe.

"It" was a cancer drug being used to treat her disease. Keller sought the treatment from her doctor even though she didn't qualify for the trial.

"It kind of struck us that if we want this, we're going to have to take some risks," Keller said.

"Now, we're taking a drug that's a little bit more dangerous, potentially, and we're using it off-label," Daniel Kantor, M.D., BScE, medical director of Neurologique in Ponte Vedra, Fla., told Ivanhoe.

Keller's doctor is one of a growing number prescribing drugs for conditions the drugs aren't FDA-approved to treat.

"We're allowed to do that as physicians," Dr. Kantor explained.

Drugs are often prescribed off-label for children and pregnant women because they're routinely excluded from trials. One recent study found the most common meds prescribed unsafely or ineffectively off-label were antidepressants and antipsychotics.

To keep yourself safe, ask your doctor if the benefits outweigh the risks and whether your insurance will cover it.

Some doctors are prescribing a cocktail of off-label drugs called Prometa to treat alcohol and drug addictions. Critics say there's no sound scientific support.

"There have only been a few published reports describing Prometa at all, and these reports are not what are called double-blind or placebo-controlled reports," John Mendelson, M.D., a senior scientist at California Pacific Medical Center Research Institute in San Francisco, Calif., told Ivanhoe.

But former addict Matt McLellan says it's helped him stay clean for a year.

"I think I'm just so blessed to have found a cure for this disease," McLellan told Ivanhoe.

Taking risks and creating options when none seem to be left.

Some insurance companies deny coverage of off-label treatments, but in some states, they are required to for cancer or other life-threatening conditions. If you and your doctor are trying to get coverage for an off-label treatment, experts say you should have your doctor provide the insurer with copies of peer-reviewed journal articles or other reliable sources that support the drug for treatment of your condition.