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SYDNEY - A drug famed for smoothing women's wrinkles may soon be soothing their period pain too.
In a world-first trial at Sydney's Royal Hospital for Women, doctors have begun injecting Botox into the womb of women with severe and prolonged monthly cramps.
Up to 10 per cent of fertile women suffer from period pain, when the uterus contracts erratically and "fights" against itself.
Professor Thierry Vancaillie from the department of endo-gynaecology said anecdotal evidence seems to show the toxic bacteria botulinum toxin can paralyse the region and bring relief.
"Like it works on the face, we believe if you inject Botox into the uterus it relaxes the muscles by stopping the nerves from working," Prof Vancaillie.
"It's really logical but it hasn't been tried yet which is amazing."
Botox is most widely used for cosmetic purposes but has also been shown to be effective in treating cerebral palsy, neck and facial spasms, chronic migraine, incontinence and chronic sweating.
A study by the hospital also found it could bring relief for women with general pelvic pain, prompting researchers to investigate other benefits of the drug.
The hospital is enlisting 20 women, aged 18 to 55, who are incapacitated by their periods -- "the kind that are down for two days a month".
"Most women can manage pain associated with periods by using over-the-counter medication, but some women are crippled by period pain," Prof Vancaillie said.
"In many of these cases there is no medical reason for the period pain, unlike women diagnosed with endometriosis, and so existing treatments are ineffective."
In the pilot study, each woman will be mildly sedated and injected with between 100 and 200 international units of Botox.
The dose, worth between $500 and $1,000, ($590 and $1170) would paralyse the lower part of the uterus for 12 to 14 weeks.
While it's too early to predict the trial's results, its success would have huge implications, he said.
"If it works, we will be able to treat this very widespread problem at the source of the pain rather than just subduing it," the researcher said.
"There are a lot of women that would love that idea, I'm sure."
The hospital will conduct a large-scale study if findings, to be presented at the end of next year, show a 60 per cent success rate.
- AAP
