“Period flu” is not a medical term. However, it does describe a series of flu-like symptoms that some people experience shortly before their menstrual period.

Once a month, in the days before a period, some people have physical and emotional symptoms that can make them feel as though they are coming down with the flu.

Period flu includes many symptoms that doctors commonly group under the term premenstrual syndrome (PMS).

Period flu remains poorly understood by healthcare professionals, and the precise underlying cause is unclear.

In this article, we examine the possible causes of period flu. We also look at the symptoms and possible treatment options.

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Period flu is not influenza, commonly known as the flu. Instead, it is a term that people use to describe the symptoms that they experience just before their period.

The symptoms of period flu are similar to those of the flu. They are also consistent with many of the symptoms of PMS.

The symptoms of period flu include:

One of the most important characteristics of period flu symptoms is that they are cyclical. They tend to present at the same time each month, just before a person has a period.

People typically report period flu symptoms after they ovulate, when estrogen levels fall, and progesterone levels rise.

Researchers have not identified a singular, specific cause of premenstrual symptoms. However, they may result from:

  • sensitivity to substances that arise as progesterone breaks down
  • progesterone affecting chemical messengers in the brain, known as neurotransmitters
  • changes in the levels of a specific neurotransmitter called serotonin

Younger people may be more likely to have period flu episodes than older people. Period flu should come to an end after menopause.

Episodes of period flu generally last no more than 2 weeks. The symptoms typically start after ovulation, in the last 2 weeks of an average 28-day menstrual cycle. Period flu symptoms usually improve after a period begins and disappear by the time it ends.

Period flu goes away permanently during menopause when a person stops menstruating.

Period flu has symptoms similar to those of the flu, and both of these conditions share symptoms with COVID-19. The only way someone can be sure whether they have COVID-19 rather than period flu is to have a test for COVID-19.

Symptoms that period flu and COVID-19 can both cause include:

  • headaches
  • fatigue
  • muscle aches
  • gastrointestinal symptoms

It is important to note that COVID-19 is an infectious disease, whereas period flu is not. People who practice physical distancing, wear masks, and wash their hands regularly may help prevent the spread of the SARS-CoV-2 virus that causes COVID-19.

Anyone who develops symptoms of COVID-19 should get a test, regardless of what point they are at in their menstrual cycle.

Self-care practices may provide some relief from period flu. Getting enough sleep is a crucial first step. According to the Centers for Disease Control and Prevention (CDC), adults need 7 hours of sleep or more each night.

Taking over-the-counter (OTC) pain relievers, such as ibuprofen or aspirin, may ease aches and pains.

Dietary changes may also help people alleviate premenstrual discomfort. These may include:

  • switching to smaller, more frequent meals to keep blood sugar levels steady
  • consuming whole grain foods, such as whole grain bread, brown rice, and beans
  • eating foods rich in calcium, such as yogurt and green leafy vegetables
  • eating foods containing plenty of polyunsaturated fatty acids, such as fish, nuts, and flaxseeds
  • cutting down on fat, sugar, and salt
  • avoiding alcohol, caffeine, and tobacco

According to the Office on Women’s Health (OWH), scientific studies on the effectiveness of alternative medicines for PMS and related conditions have produced mixed results. However, the OWH note that some people report improved symptoms with herbal supplements, such as:

  • evening primrose oil
  • black cohosh
  • chasteberry, which people taking hormonal medication should not use

Other practices that may help reduce period flu symptoms include:

  • yoga
  • massage
  • meditation
  • deep breathing

Although many people experience period flu or PMS at some point in their lives, it affects some individuals more severely than others.

Treatments options for severe cases of period flu include:

  • prescription pain relievers for muscle and joint pain
  • diuretics for water retention
  • hormone medications that improve symptoms by affecting hormone levels
  • antidepressants for psychological conditions that period flu may cause

Period flu may cause a person discomfort and make them worry that they might have the flu. However, most people do not need to see a doctor or take prescription medication.

Some experts recommend seeing a doctor for premenstrual symptoms if they interfere with the ability to perform daily activities.

According to the American College of Obstetricians and Gynecologists, engaging in 30 minutes of aerobic exercise on most days may help reduce the symptoms of period flu.

Aerobic exercise includes activities that increase the heart rate and cause rapid breathing. Biking, swimming, running, and brisk walking are all aerobic activities.

Period flu describes a group of symptoms that some people experience just before their period. It has a connection to changes in hormone levels during a person’s menstrual cycle. Some of the symptoms, such as body aches and fatigue, can make people feel as though they are coming down with the flu.

Although period flu is not contagious, unlike influenza, it does cause discomfort.

People can usually manage their symptoms with self-care, dietary changes, and OTC medicines. A doctor’s advice may be helpful if period flu is interfering with a person’s ability to carry out their daily activities.