Your Month-by-Month Guide to Hives Triggers

by Beth Shapouri Health Writer

For the 20% of folks that get hives (or urticaria), they seemingly pop up out of nowhere. But there’s always a trigger—and if you’re prone to them, it can be hard to keep on top of all the potential causes. So, we broke down some of the major offenders by month, all in the name of helping you head off those quick-passing welts before they start. From bug bites in the summer to frigid temps and heavy clothing in the winter, this is your breakdown of the seasonal triggers that may be causing your hives.

icicles
iStock

January Trigger: Freezing Temps

With the coldest day of the year occurring in most states in January according to the National Centers for Environmental Information, if you’re hives-prone it’s time to be a little extra careful when going outdoors to avoid getting a specific type of temperature-induced hives called cold urticaria. While Dr. Madfes says we don’t quite know how chilly temps are a trigger, we do know that limiting time outdoors and bundling up—in cotton—can help as the mercury drops.

dry skin
iStock

February Trigger: Dry Skin

As the cold months drag on, the weather can start to take a toll on the skin, leaving it parched. And since, again, the act of scratching can trigger the response that brings on welts, anything that makes you itchy is a good thing to avoid. Dr. Madfes says to keep skin moisturized with shea butter- or ceramide-infused creams. Another thing that helps is to take omega-3 and omega-6 supplements (1 gram each) along with vitamin C (1,000 mg) daily as a preventative measure. As always though, get the ok from your doctor first.

running in Lycra
iStock

March Trigger: Outdoor Exercise

If you like to take your sweat sessions outside, heads up: Both heat and exercise can trigger hives in people who are prone to them thanks to the irritation caused by friction. That’s why folks who live in the southern states may find themselves with welts in the spring, while the northern states follow later. Avoiding sweating it out during the highest temps of the day is a good idea. And stay away from synthetic fabrics like lycra. “Cotton or cotton blends are the best to wear,” says Dr. Madfes. “Also bring an extra shirt to swap out after exercise.”

pollen
iStock

April Trigger: Pollen

Spring is a big time for allergies, in large part thanks to tree pollen and spring weeds, according to Dr. Dass. Since these tiny little pollen specks are lightweight enough to travel with just a light wind and end up landing on things you can come in direct contact with, they can be hard to avoid. Your best bet for holding off a hives flare? Dr. Dass says to see your doctor for a recommended antihistamine, such as Claritin, Zyrtec or Allegra.

wood tick
iStock

May Trigger: Bug Bites

As warmer temps start to show up, so do insects—and due to the body’s response to the proteins introduced via their bites, so can hives as part of the histamine reaction. If you have a severe response, be sure to see your doctor for proper medications. Otherwise, Dr. Dass says, “It is important to try to be preventative by applying bug spray or wearing bug-repelling bracelets, wearing lightweight long sleeve shirts, and avoiding areas with large bodies of water and strong perfumes.”

grass
iStock

June Trigger: Grass

In the summertime, grass pollen is at its peak—and if you happen to be allergic to any of the types in your region, Dr. Dass explains that just touching the stuff can provoke a flare-up. Your plan for a happy June? Staying off those green blades and watching the grass pollen count to determine which days it’s better to stay inside to avoid its residue.

mold
iStock

July Trigger: Mold

Now, outdoor mold is a year-round trigger for many—and can trigger hives if you encounter it while gardening or otherwise interacting with nature—but since it grows in humidity and warmth, this common, hives-inducing allergen can hit its peak in late summer, according to the American Academy of Allergy Ashtma and Immuniology. Also look for it to spike in the spring—and in October in the cooler states where fallen leaves can harbor the fungus.

heat wave
iStock

August Trigger: Heat Waves

Heat is a cause of hives on its own, but there’s another element that could make for a recipe for hives on the hottest days of the year: “Sweat accumulates on the skin and dries out leaving the residue behind—that can dry [and irritate] the skin,” explains Dr. Madfes. Your go-to strategy: Try seeking shelter in air conditioning whenever you can—and stay in the shade when you can’t.

common cold
iStock

September Trigger: The Common Cold

September ushers in the start of cold season, which can set off welts as it taxes the immune system. Any illness can cause hives the same way that stress and anxiety can, according to Dr. Madfes, by way of the sympathetic nervous system, which steps up the production and release of histamine. And colds are singled out because they are so common. One way to head off a case of the sniffles (and the hives that may follow): Wash your hands. Hey, it’s something we’re all very used to doing these days.

ragweed
iStock

October Trigger: Ragweed

There’s a reason it seems like October is a sneeze-fest. “Fall is when ragweed is at its peak,” says Kathleen Dass, M.D., an allergist and immunologist with DMC Harper University Hospital in Oak Park, MI. It’s most common for hives to pop up when in direct contact with the plant’s pollen while you’re outside, stimulating the skin’s mast cells. But it is also possible to get them as part of an overall allergic episode when the pollen is inhaled, and the immune system releases an antibody called IgE. Best bet for ragweed sufferers: Ask your doc for a prescription allergy medication, says Dr. Dass.

citrus fruit
iStock

November Trigger: Citrus Fruit

Oranges, tangerines, and many other citrus fruits are in season in late fall, which can bring on hives both due to citrus allergies and for another reason: Explains Dr. Dass, citrus fruits are known triggers from “pollen food syndrome” or “oral allergy syndrome,” in which the pollen from one plant is similar enough to other allergens like fruits, vegetables, legumes, and tree nuts that the body to confuses the two. One strategy that may help if you suspect the second scenario is happening to you: Eat it cooked, in, say, a jam-form, which Dr. Dass explains destroys those potentially problematic plant proteins.

wool coat
iStock

December Trigger: Wool

As people break out their wool coats, hives can come a-knocking. Even if you’re not reactive to the actual makeup of the wool, it’s itchy. That matters because “scratching triggers mast cells in your skin to release histamine and other inflammatory activators,” says Diane Madfes M.D., a New York City-based dermatologist and assistant clinical professor of dermatology at Mt. Sinai School of Medicine. If this is a problem for you, it’s time to check out an alternative fabric with smoother fibers like cotton.

Beth Shapouri
Meet Our Writer
Beth Shapouri

Beth Shapouri is an award-winning beauty, health, wellness, and lifestyle freelance writer whose work has appeared in Glamour.com, Elle.com, Health Monitor, Magnolia Journal, Marie Claire, RealSelf.com and more. Career highlights include a multi-year stint as Lead Beauty Writer for Glamour.com and contributing to a New York Magazine package on circumcision that received a National Magazine Award for service.