A teenager nearly died after suffering toxic shock syndrome - as a result of using a tampon.

Shannon Turner was just 15 when she experienced vomiting, diarrhea, a fever and fatigue, all symptoms of toxic shock syndrome. The rare condition, which can be life threatening, is caused by an infection, and can happen when using a tampon or menstrual cup, or from an infected wound.

She said: "It put me in a coma and nearly took my life - I hadn’t even had my period for a full year yet... I was brought to the doctor that afternoon, given a shot for nausea, and sent home.

"I continued to deteriorate and was brought back to the doctor later that same day. My last memory is collapsing in the office and laying on the ground because it hurt too much to sit up."

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The ordeal happened one day after Shannon returned home from holiday, and so she put her symptoms down to jetlag initially. However, the teenager, from the US, fell into a coma and doctors worked tirelessly to diagnose her.

"My heart rate was extremely high, my blood pressure was dangerously low, and I was rushed to the ICU. I didn’t wake up until a few days later... Thankfully, my mum mentioned to a family member that I was on my period - and that’s when menstrual toxic shock syndrome (mTSS) was suggested," Shannon continued.

According to MayoClinic, toxic shock syndrome's risk factors include skin wounds, surgery, and the use of tampons and other devices, such as menstrual cups and birth control sponges or diaphragms.

Shannon was put on the right treatment plan, though, just at the time when she had been given a 50-50 chance of survival. The teen stayed in hospital for several days after the doctors saved her life, but says she was sent home with "little guidance" on what to expect during recovery, or how long her symptoms would last.

Speaking to Mail Online today, Shannon added: "I dealt with memory loss, anxiety, attention issues, and depression. My periods also became extremely painful... From the age of 15, I was put on prescription painkillers to manage my menstrual pain."

Her experience led to her starting her nonprofit, Protect Her Inc., which is dedicated to "revolutionising menstrual health education."

"We believe knowledge is power - and yet, so many people are navigating their cycles with almost none. I began to see why [there were no recourses], because periods have been taboo for far too long. It’s the same reason I never talked about my experience with mTSS, and that silence was incredibly isolating," Shannon said.

"My message to anyone using tampons is: use the lowest absorbency possible. Your tampon should be saturated when you remove it - if your flow is light, opt for a liner instead." She also advises against using tampons overnight, noting if you begin to get sick you won't notice the symptoms if you're asleep.