PMS is the worst. It seems to sneak up on you every month like clockwork — even though you know approximately what’s coming and when to expect it. Maybe you’ve enlisted natural remedies like probiotics and exercise. Or maybe you’ve tried couples therapy to reduce your PMS symptoms. But if, despite all of your defenses, you still find yourself feeling really under the weather around that time of the month, you’re not alone. (Yet another reason why you really need to talk about your period.) The internet is full of people trying to get to the bottom of cold- and flu-like symptoms that coincide with their monthly cycles: things like sinus pain, dizziness, fevers, head and body aches, and stuffy noses.
There’s a simple reason for all of these symptoms, but you’re not going to like it: hormones. According to Dr. Nieca Goldberg, Medical Director of the Joan H. Tisch Center for Women’s Health at the NYU Langone Medical Center, “Hormonal changes prior to your period can cause a range of symptoms, fatigue, abdominal cramping, bloating, back pains, and other body aches.” In other words, it’s all connected. One sufferer’s cramps have the same root cause as someone else’s headache. Dr. Goldberg explains that these symptoms “may be due to hormonal changes [like] lower levels of estrogen around your period.” Estrogen levels fall the week before your period — hence the achy aspects of PMS. There are knock-on effects for other hormones, including the ones that regulate sleep — so sleep deprivation might explain the fatigue.
Dr. Molly O’Shea has another answer: prostaglandins. “Prostaglandins can cause intestinal cramps, diarrhea, nausea, vomiting, a feeling of being flushed, and general achiness.” Since these chemicals can also impact your body’s temperature, they’re likely responsible for the flu-like fluctuations between warm and chilly. These temperature shifts might feel like a fever, but a quick thermometer reading should reassure you that everything is just fine.
Luckily, “period flu” is a lot easier to treat than the real one. (Gentle reminder: You need a flu shot to prevent that.) “For the body aches and cramping, over the counter medication such as ibuprofen or naproxen may help,” says Dr. Goldberg. “Treatment should be based on the severity of the symptoms and you should speak to your GYN, particularly if the symptoms keep you from work or your activities.” And if you’re not sure what painkiller is right for your symptoms, check our guide to avoiding wrong and harmful period cramp meds.
Above all, keep an eye on your symptoms, just in case they’re trying to tell you something. “Unlike the flu, these symptoms do not cause fever, and they improve after your period,” clarifies Dr. Goldberg. “So if you have a fever or the symptoms do not improve, you need to see your doctor.”