What You Should Know About the Period Flu

It's not contagious, but it can make you feel downright miserable.

"Period flu" is not an official medical term, nor is it the typical "flu," the contagious respiratory virus that hits hard in the fall and winter. But for people who experience period flu in the days before their period, the name fits well. That's because the signs can feel a lot like the flu. Or it can feel like you're about to come down with the flu—including headache, fever, digestive distress, and fatigue, among flu-like other symptoms.

"[Period flu is] kind of similar to PMS [premenstrual syndrome] symptoms, but it's a little bit more exaggerated," Tamika K. Cross, MD, an OB-GYN at Opulence Health and Wellness in Pearland, Texas, told Health.

And just like PMS, period flu typically strikes at the same point during your cycle: after ovulation and before your period, according to Dr. Cross. Some health professionals even consider period flu to be part of PMS. Here's what you need to know about the symptoms, causes, and treatments for period flu.

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What Is Period Flu?

There are not any official criteria to diagnose period flu because it's not an actual medical condition. But generally, period flu can lead to many symptoms that are familiar to PMS, such as breast tenderness, irritability, and fatigue, Kelly Culwell, MD, board-certified OB-GYN and women's health expert, told Health.

Other common symptoms are reminiscent of the real flu—including joint pain, muscle aches, low-grade fever, nausea, headaches, and dizziness.

Those symptoms typically begin either right before or at the start of your period. You may even notice those flu-like symptoms while you are ovulating, which occurs approximately two weeks before menstrual bleeding. Symptoms usually resolve after one to three days. Also, once your flow decreases, period flu symptoms also decrease, said Dr. Cross.

What Causes Period Flu?

There's no single, clear-cut cause for period flu. Experts "don't 100% know" what's behind the cluster of symptoms, explained Dr. Cross. But the likely culprit? Hormone fluctuations.

"The sudden drop in hormones during the time between ovulation and [your] period is the cause of PMS symptoms, including period flu," explained Dr. Culwell.

While estrogen decrease during that time frame, hormone-like chemicals, called prostaglandins, increase. Prostaglandins are chemicals that trigger the uterine muscles to contract, which causes the tissue that lines the inside of the uterus (called the endometrium) to shed during menstrual bleeding and induces painful cramps.

Prostaglandins "can also cause abdominal cramps and diarrhea," noted Dr. Culwell. Some people may describe their period flu symptoms as in line with the "stomach flu" (which is not a real diagnosis but a colloquial term for norovirus).

Those chemicals may also be the culprit of a low-grade fever. In one study published in 2016 in the journal Temperature, researchers found prostaglandins may affect neurons in the hypothalamus, which is the part of your brain that regulates your body temperature. And that can cause you to feel like your body is fighting off a virus when it isn't. Your body temperature also increases when you are ovulation, per the Office on Women's Health.

Additionally, hormonal fluctuations influence your brain chemistry, causing levels of the neurotransmitter serotonin to fluctuate. That, in turn, can lead to a variety of symptoms—including the kind of fatigue that happens when you get the real flu, noted Dr. Cross.

Treatments for Period Flu

Options are available to help vanquish period flu—or at least ease the severity of the symptoms.

First up: Over-the-counter nonsteroidal anti-inflammatory medications (NSAIDs), such as Advil or Motrin (ibuprofen) and Aleve (naproxen). NSAIDs also decrease the number of prostaglandins in your body, according to a study published in 2018 in the Eurasian Journal of Medicine.

Lifestyle modifications can also be effective, noted Dr. Cross. These include drinking more water and exercising; opting for certain foods, such as whole grains and vegetables; and getting enough sleep. You can also try applying a heating pad to your abdomen, or wherever you experience muscle aches, to alleviate pain.

"Rest, fluids, pain medications, and anti-inflammatory medications like Tylenol or ibuprofen will usually help treat the symptoms," agreed Dr. Culwell.

According to the Johns Hopkins Medicine Health Library, avoiding smoking, drinking alcohol, and consuming too much caffeine can also help mitigate symptoms of premenstrual dysphoric disorder (PMDD), a condition that causes similar but more severe symptoms than PMS. Those lifestyle changes may also work for avoiding period flu.

Ultimately, no single medication or modification can end period flu. Instead, the goal is to treat your symptoms. Sometimes those first-line, low-level treatment options don't do the trick. In those situations, birth control pills can help by regulating hormone levels, explained Dr. Cross.

"If the symptoms are really impacting your quality of life—such as [being] unable to work, go to school, or participate in normal activities—you should talk to your healthcare provider about possible prevention options like hormonal birth control," added Dr. Culwell.

How To Prevent Period Flu

Similar to lifestyle changes that can treat uncomfortable symptoms, you can take steps to prevent period flu. According to the Johns Hopkins Medicine Health Library, those lifestyle changes include:

  • Eating healthily—specifically increasing your intake of protein and decreasing your intake of sugar and caffeine
  • Taking vitamin B6, calcium, and magnesium supplements
  • Exercising regularly

When To See a Healthcare Professional

Don't hesitate to tell your healthcare professional if period flu symptoms strike hard during each cycle or linger longer than a few days.

Along with proposing treatment options, your healthcare provider may also check to make sure there isn't another medical issue—like the actual flu or other conditions that also cause PMS-like symptoms, such as chronic fatigue syndrome or depression—according to Dr. Cross.

Ultimately, the period flu can be miserable. But unlike the actual flu—which can leave you sidelined with chills, body aches, a sore throat, and nasal congestion—period flu is not contagious and unlikely to lead to anything serious.

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  1. Conti B. Prostaglandin E2 that triggers fever is synthesized through an endocannabinoid- dependent pathwayTemperature (Austin). 2016;3(1):25-27. doi:10.1080/23328940.2015.1130520

  2. Office on Women's Health. Your menstrual cycle.

  3. Gunaydin C, Bilge SS. Effects of nonsteroidal anti-inflammatory drugs at the molecular levelEurasian J Med. 2018;50(2):116-121. doi:10.5152/eurasianjmed.2018.0010

  4. Johns Hopkins Medicine. Premenstrual dysphoric disorder (PMDD).

  5. Johns Hopkins Medicine. Premenstrual syndrome (PMS).

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