Now, doctors are further stretching the drug's usefulness by treating patients who experience certain type of hyperlacrimation -- in other words, the overproduction of tears in response to certain stimuli.
For 58-year-old Patricia Webster of Maidstone, England, who had been living with the degenerative nerve condition known as Guillain-Barre syndrome, the occasional shot straight into her tear ducts means freedom from an embarrassing symptom of her condition in which she would appear to cry whenever she ate.
"For the last 18 years of my life I've done nothing, and the embarrassment of my eyes was a major part of this," she told ABCNews.com.
Still, even Webster was skeptical when her doctor first offered up the treatment.
"Of course, I'm thinking, 'Botox ... it's a cosmetic treatment.' I thought, 'He's not worried about my eye, he's telling me that I'm wrinkly,'" Webster said.
In addition to hyperlacrimation, some doctors are also using Botox to help relieve chronic pain.
Many glaucoma patients using an eye drop known as bimatoprost to improve their vision have enjoyed an unexpected side effect -- thicker, more luxurious eyelashes.
The effects of the medication were so pronounced, in fact, that the FDA recently approved the drug for this cosmetic use. Allergan, the company that manufactures the glaucoma drug known as Lumigan, rebranded it under the new name Latisse.
Dr. Scott Whitcup, Allergan's executive vice president of research and development, told ABCNews.com that researchers noted the eyelash-enhancing side effects of the eye drops during the Phase 3 trials for the drug.
"At the time, we began thinking of developing Lumigan as a treatment for eyelash growth," Whitcup said.
Essentially, the drug works by keeping hairs in their growth phase -- the phase during which they become longer, thicker and darker. Of course, the eyelash-enhancing effects of Latisse are not permanent once the drug is discontinued. And at $120 for a 30-day supply, Latisse is not cheap. But it is still far cheaper (and most likely less risky) than surgical procedures designed to achieve the same end.
Strange but true: When it comes to trying to get pregnant, some women look to a remedy more associated with coughs and colds than conception. That remedy is Robitussin.
So far there is no reliable evidence to show that the syrup does much, if anything, to increase the odds of a woman getting pregnant. The theory, however, is that in much the same way the drug can thin the mucus in your nose and throat, it may also thin the cervical mucus. Thinner cervical mucus means that sperm may have an easier time making it into the uterus to fertilize a waiting egg.
While proof of this remedy remains elusive, it is far from the only home-grown cure that many women look to when it comes to getting pregnant. Some aspiring moms try dietary changes, for example. But because so many factors contribute to a woman's ability to conceive, doctors warn that changing any one variable is not likely to have a huge overall effect on the chances of pregnancy.
Among the plethora of drugs used in the cosmetic realm, it's a safe bet that few would recognize the name phosphatidylcholine. But in many clinics around the world, this soybean-based, FDA-approved treatment to break down fat in the blood is also being injected under the more familiar names lipostabil or lipodissolve as a surgery-free fat buster.