Why Do My Allergies Get Worse at Night?

Allergy triggers and symptoms are unique to each individual. Allergies can depend on your body, environment, and even geographic location. Various factors can cause allergy symptoms to worsen in the evening for many people. You may spend the day with few or no allergy symptoms, only to experience sniffles and itchy eyes when you go to bed. Allergy symptoms can get worse at night because one of the places where dust and pet dander build up are your mattress. If you have seasonal or environmental allergies, your symptoms may come and go at different times of the day. You may experience worse nighttime allergies, morning allergies, or even both.

What are possible triggers of nighttime allergy symptoms?

Any type of allergy can ruin your sleep. Rash, food allergies, or an upset stomach triggered by allergies can cause sleep problems. However, the most common pair of sleep-destroyers are nasal allergies and asthma, and there are multiple potential triggers for nighttime allergy symptoms, including the following:

Pollen: This is one of the most common allergens affecting millions of people in the United States. Pollen particles can travel anywhere and can be transported into houses through insects and wind through open windows. They may settle on the skin, hair, clothes, or shoes and stick to pillows and bedsheets. Researchers found that certain types of pollen, which are usually suspended higher in the atmosphere while air is warm, tend to fall closer to the ground level during cool hours at night. If you sleep next to an open window, you may be exposed to these, which worsen your allergy symptoms.

Dust mites: Dust mites find their home in mattresses, pillows, and bedding. People with asthma and other allergies could have a dust mite allergy. Dust mites cause symptoms such as itchiness, breathlessness, chest tightness, coughing, wheezing, eye itchiness and redness, stuffy nose, and sneezing.

Mold: Mold thrives in dark, moist places where it is seldom checked and cleaned, such as under and behind beds. Bedrooms tend to be the most allergenic part of houses. This is especially true if bedrooms are close to bathrooms. If you're allergic to mold, then it could trigger your allergies and keep you up at night.

Pet dander: People often sneak their pets into their beds. As a result, their beds tend to have higher concentrations of pet dander. People allergic to pet dander can have instant reactions or long-term symptoms. Even in the absence of the pet, pet dander allergic reaction may take occur. Dander can travel and land on lots of household and bedroom surfaces. This means that even if you don't own a pet yourself, you can bring the dander home with you and then have to deal with allergy symptoms for days, maybe even longer.

What causes allergy symptoms to feel worse at night?

Sleeping on your back often encourages the flow of postnasal drip into the throat, causing a tickle in your throat as you sleep. Nasal blockages and runny noses are common occurrences among people with allergies, and they disrupt sleep during night. As we lie down, the mucus in our nose travels backward toward the throat. This can, in turn, lead to coughing and make it hard to sleep. Allergens on the bed may irritate the skin and cause itching on any part of the body (nocturnal pruritis).

Research was conducted on how chemicals released during the body's immune response to allergens affect allergy symptoms at night and disrupt sleep. The sleep-wake cycle, which controls the cadence of sleep and wakefulness, is controlled by a large number of hormones. Some of these hormones are also involved in regulating allergic reactions. A reason why allergies are worse, particularly at night, is that certain allergy-regulating hormones dip when you approach deeper stages of sleep.

Tips to reduce allergies at night

To reduce allergies at night, keep your surrounding allergen-free.

  • Wash bedsheets on a weekly basis. Deep clean the entire bedroom and carpets and wipe down hidden surfaces every month to get rid of mold, dust mites, and pet dander.
  • Use dust mite covers on the bed to keep dust mites away.
  • Invest in anti-allergy bedding that uses specifically manufactured fibers to keep allergies at bay.
  • Use high-efficiency particulate absorbing (HEPA) filters. Air purifiers are recommended as a way to remove allergens. Take over-the-counter medicines that contain histamines.


Common Allergies: Symptoms and Signs See Slideshow
Meyer, Mary Leigh. "You Asked: Why is My Asthma Worse at Night?" Vital Record. Mar. 13, 2019. <https://vitalrecord.tamhsc.edu/you-asked-why-is-my-asthma-worse-at-night/>.