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Women living with stoma bags have welcomed a new trial which will see signs put up outside accessible toilets raising awareness of hidden conditions.
Amber Davies, 23, from Builth Wells, told ITV News she has faced a "number of scenarios" where she has been challenged for using accessible toilets to change or empty her stoma bag which made her feel "uncomfortable".
Amber, a student at Cardiff University, said sometimes her bag needs to be changed up to 15 times a day - and described her illness as "chronic, debilitating" and "lifelong".
On one occasion, Amber was accused of taking drugs in a disabled toilet while on a night out in Birmingham.
She took to social media to write an open letter detailing her experience and calling for a better understanding of her condition.
"People often don't see or understand there could be something deeper going on and often jump to conclusions and follow stereotypes before taking a step back.
"On a night out, people do jump to conclusions and think you're using accessible facilities for the wrong reasons - dealing drugs, having sex."
"It can be really difficult because it's largely invisible - the reasons behind needing the stoma and the stoma itself. To others you look "quite normal" - a young healthy person - when it isn't always the case."
Amber welcomed a new initiative by Cardiff Council which will see new signage put up outside accessible toilets around the city under the banner #BeTheChange.
The signs are designed to help support people living with hidden illnesses such as Alzheimer's, a stoma and anxiety. The council says 92% of people who need to use an accessible toilet don't have a visible illness.
"We're all guilty of jumping to conclusions. It won't only prompt people to think before they speak but educate people as well there are hundreds of invisible disabilities", Amber said.
Rachel Allen and her son Jake both live with a stoma bag.
She said the introduction of the signs is "absolutely huge".
"I've had tutting behind me, looks - people judging me. As I stand here today you wouldn't think I had anything under my clothes, but I do.
"Those 92% are not represented with that wheelchair logo on those toilets - and that's why this sign is so important."
What is a stoma?
More than 102,000 people in the UK have a stoma and will wear a stoma bag either temporarily or for the rest of their life, according to the British Medical Journal.
A stoma (ostomy) is an opening on the wall of the abdomen that diverts the contents of the bowel out of the body. A bag fits around the stoma to collect the contents.
You may need a stoma if: • severe Crohn's or Colitis that is not responding to medical treatment• complications of your disease that will not respond to medical therapy• a perforated bowel• a high risk of cancer in the bowel• cancer in the bowelSome people choose to have a stoma if they feel it will improve the quality of their lives.
If you have an ileostomy, you will wear a stoma bag that opens at the bottom so you can empty it. An ileostomy produces semi-liquid waste continuously, so the bag often needs to be emptied several times a day.
Crohn's and Colitis UK has more information on its website about living with a stoma.