Many people wonder if it is safe to sleep with a tampon in. Most people will be fine if they sleep while wearing a tampon, but if you sleep for longer than eight hours, you could be at risk of toxic shock syndrome (TSS). This is a rare but potentially fatal condition that requires urgent medical attention.

To avoid toxic shock syndrome, you should ideally change your tampon every four to eight hours, and use a tampon with the lowest absorbency you need. Alternatively, use pads or a menstrual cup instead of tampons while you sleep.

While toxic shock syndrome is rare, it’s serious and potentially fatal. It can affect anyone, not just people who use tampons.

It can occur when the bacterium Staphylococcus aureus gets into the bloodstream. This is the same bacterium that causes a staph infection, also known as MRSA. The syndrome can also occur due to toxins caused by group A streptococcus (strep) bacteria.

Staphylococcus aureus is always present in your nose and skin, but when it overgrows, an infection can occur. Usually the infection occurs when there’s a cut or opening in the skin.

While experts aren’t entirely sure how tampons can cause toxic shock syndrome, it is possible that the tampon attracts bacteria because it’s a warm and moist environment. This bacteria can enter the body if there are microscopic scratches in the vagina, which could be caused by the fibers in tampons.

High-absorbency tampons can be riskier, possibly because it absorbs more of the vagina’s natural mucus, drying it out and increasing the chances of creating small tears in the vaginal walls.

The symptoms of toxic shock syndrome can sometimes mimic the flu. These symptoms include:

  • fever
  • headaches
  • muscle aches
  • nausea and vomiting
  • diarrhea
  • dizziness and disorientation
  • sore throat
  • rashes or sunburn-like marks on your skin
  • low blood pressure
  • eye redness, resembling conjunctivitis
  • redness and inflammation in your mouth and throat
  • peeling of skin on the soles of your feet and palms of your hands
  • seizures

Toxic shock syndrome is considered a medical emergency. If you have it, you’ll likely be treated in an intensive care unit for several days. The treatment for toxic shock syndrome can include an intravenous (IV) antibiotic and a course of antibiotics at home.

In addition, you might receive medicine to treat the symptoms of toxic shock syndrome, such as an IV to treat dehydration.

While toxic shock syndrome is associated with tampon use, it’s possible to get it even if you don’t use tampons or menstruate. Toxic shock syndrome can affect people no matter their gender or age. The Cleveland Clinic estimates that half of all toxic shock syndrome cases are not related to menstruation.

You’re at risk for toxic shock syndrome if you:

  • have a cut, sore, or open wound
  • have a skin infection
  • recently had surgery
  • recently gave birth
  • use diaphragms or vaginal sponges, both of which are forms of contraception
  • have (or have recently had) inflammatory illnesses, such as tracheitis or sinusitis
  • Have (or have recently had) the flu

If you tend to sleep for more than eight hours at a time and you don’t want to wake up to change your tampon in the middle of the night, it might be best to use a pad or menstrual cup while sleeping.

If you use a menstrual cup, be sure to wash it thoroughly in between uses. There has been at least one confirmed case linking menstrual cups to toxic shock syndrome, according to a 2015 case study. Wash your hands whenever handling, emptying, or removing your menstrual cup.

Toxic shock syndrome is much less common than it once was, according to the Rare Disease Database. This is partly because people are more aware of the condition today, and because the Food and Drug Administration (FDA) has regulated the absorbency and the labeling of tampons.

According to Cleveland Clinic, toxic shock syndrome was first identified in 1978. In the early 1980s, toxic shock syndrome was linked to the use of super-absorbent tampons. Because of this, manufacturers started reducing the absorbency of tampons.

At the same time, the FDA stated that tampon package labels had to advise users not to use super-absorbent tampons unless absolutely necessary. In 1990, the FDA regulated the labeling of absorbency of tampons, meaning that the terms “low absorbency” and “super-absorbent” had standardized definitions.

This intervention worked. Forty-two percent of tampon users in the United States used the highest absorbency products in 1980. This number went down to 1 percent in 1986.

In addition to the changes in how tampons are manufactured and labeled, there has been a growing awareness of toxic shock syndrome. More people now understand the importance of changing tampons frequently. These factors have made toxic shock syndrome far less common.

According to the Centers for Disease Control and Prevention (CDC), 890 cases of toxic shock syndrome in the United States were reported to the CDC in 1980, with 812 of those cases related to menstruation.

In 1989, 61 cases of toxic shock syndrome were reported, 45 of which were associated with menstruation. Since then, the CDC says even fewer cases of toxic shock syndrome are reported annually.

Toxic shock syndrome is serious, but there are a number of precautions you can take to prevent it. You can prevent toxic shock syndrome by:

  • changing your tampon every four to eight hours
  • washing your hands thoroughly before inserting, removing, or changing a tampon
  • using a low-absorbency tampon
  • using pads instead of tampons
  • replacing your tampons with a menstrual cup, while being sure to clean your hands and your menstrual cup often
  • washing your hands frequently

If you have any surgical incisions or open wounds, clean and change your bandages frequently. Skin infections should also be cleaned regularly.

If you fall into one of the at-risk groups for toxic shock syndrome, and you have any symptoms, call an ambulance or go to the emergency room immediately. While toxic shock syndrome can be fatal, it is treatable, so it’s important that you get help as soon as possible.

While it’s generally safe to sleep with a tampon in if you’re sleeping for less than eight hours, it’s important that you change tampons every eight hours to avoid getting toxic shock syndrome. It’s also best to use the lowest absorbency necessary. Call a doctor if you think you may have toxic shock syndrome.