When most people think of Botox, they think of how it erases frown lines between the brows and makes crow’s feet disappear. But Botox is more than just a cosmetic fix.

This month, researchers announced that Botox is a more effective treatment than steroids for plantar fasciitis, a condition where the connective tissues on the sole of the foot become inflamed. When doctors inject Botox into the calf muscles it thins them, causing them to pull less on the plantar fascia and reducing the pain.

And last week, the Food and Drug Administration approved Botox to treat overactive bladder, a condition where the muscles of the bladder squeeze, leading to frequent urination and incontinence. Botox relaxes the bladder, reducing the urgency.

 “The mechanism of action is the same. [Botox treats] so many indications and various problems—cosmetic and overactive muscles,” says Dr. Anthony Youn, a plastic surgeon and assistant professor of surgery at William Beaumont School of Medicine. (Youn is also a frequent contributor to NBCNews.com and TODAY.com.) “[It helps] medical conditions where if you relax muscles that condition improves, like headaches or overactive bladders.”

What else can Botox do? Let's find out.

Migraines
For some migraine sufferers, traditional treatments fail and they experience extreme pain. Plastic surgeons, like Dr. Anne Taylor, noticed that some of their patients who used Botox for wrinkles would schedule visits when they felt migraines starting.

“I had been in practice for 15 years before it was released for migraines and I [had patients who said] ‘I have a migraine coming’ and had to come in and get Botox,” explains Taylor an associate professor at the Ohio State University Medical Center. 

While physicians knew that Botox alleviated migraine pain, the FDA only approved its use for headaches in 2010. 

The reason it works is because the nerve fibers take the Botox and the toxin cleaves a protein that is needed to release a neurotransmitter, says F. Michael Cutrer a neurologist at the Mayo Clinic. The neurotransmitter causes the spasms or muscle tightness that causes headaches, wrinkles, or twitches.

“A reasonable percentage of these people were not responsive to [traditional treatment]. I would say 50 to 60 percent show [improvements with Botox]. Some of these people’s lives are completely changed,” Cutrer says.

All Botox treatments, cosmetic or therapeutic, last anywhere from three to six months and most people need several treatments per year.

Sweating
A woman visited Taylor’s office—she needed to get electronic fingerprints for a job she applied to, but every time she attempted the fingerprinting it failed because her digits were slick with sweat. The patient wondered if there was anything Taylor could do. Taylor had been injecting Botox into armpits to treat hyperhidrosis, excessive sweating, so she thought Botox could help.

“[Excessive sweat] is debilitating for the heavy sweaters,” says Taylor. “[Botox] works every time. It’s really fantastic.”

After Taylor injected all the woman’s fingers with Botox, the woman’s hands were noticeably dry and she could successfully get fingerprinted.    

“It works … because it deactivates the nerves that control the sweat glands,” Cutrer says. 

Weight loss
For more than 10 years, Dr. Anthony Kalloo — the Moses and Helen Golden Paulson Professor of Gastroenterology at Johns Hopkins Hospital — has used Botox to treat patients suffering from GI problems where the muscles clench up and spasm. The Botox relaxes the muscles, preventing the twitches. When he injected the Botox in the stomach he noticed something else—the food moves through slower, making a person feel fuller longer, meaning he eats less. He thought this would be a way to encourage weight loss.

“The weight loss is moderate. Patients lose 20 to 30 pounds in four to six months,” he says. Because Botox is reversible he pairs his weight-loss treatment with a plan that includes exercise and healthy eating habits. (It turns out eating less does not shrink the stomach; it’s just a cruel urban legend.)

Kalloo uses an endoscope, a long medical scope that is inserted orally, to inject the stomach from top to bottom with Botox. The procedure takes about 10 minutes and patients are in a twilight sleep, where they can’t feel pain, but aren’t completely unconscious. While he notes a recent research paper found that Botox did not work, previous studies have shown it’s effective (the FDA has yet to approve its use for weight loss). He believes that more work needs to be done, but thinks Botox shows promise.

“We use a noninvasive method like endoscopy to enable a surgery-like result,” he says. “I think that this is the future of weight loss intervention.”  

Square jaws and bulky calf muscles
When some women look in the mirror, they cringe at the sight of their square jaws. While traditional plastic surgery can soften the jaw line, doctors in Asia, and increasingly in the United States, inject Botox in the face to thin the muscles.

“If they feel like their jaws are too square or wide they can narrow the jaw line [with Botox],” says Youn. “The good and bad thing is the results of Botox last anywhere from three to six months.”

Doctors also use it to shrink the calf muscles for those complaining of bulky legs. This might prevent patients from running as fast or jumping as high, but it doesn’t last.

The FDA hasn’t approved Botox for these uses, but that doesn't necessarily mean they are less safe -- for example, using Botox to treat crows’ feet isn’t approved, but is a common treatment.

Hair loss
A few years ago, a woman approached Cutrer of the Mayo Clinic for help. She had suffered from a viral infection and afterward she had areas about the size of quarters on her scalp where she felt extreme pain. When he examined her, he noticed the painful spots were bald. He thought he would try Botox on the areas to see if it alleviated the pain. 

 “The pain went away and the hair re-grew,” he says. “If I hadn’t seen it I wouldn’t have believed it.”

He published a paper about this case in the journal Cephalalgia. 

While Cutrer does not recommend Botox for balding, considering there are many other treatments, he notes that after her Botox therapy stopped, she lost her hair again.

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