(Tiếng Việt) Tìm hiểu về dị ứng thời tiết

Seasonal allergies

Hay fever occurs when your immune system overreacts to an outdoor allergen, such as pollen. The most common culprits are pollens from wind-pollenated plants, such as trees, grasses, and weeds. The pollens from insect-pollinated plants are too heavy to remain airborne for long, and they’re less likely to trigger an allergic reaction.

Seasonal allergies are less common during the winter, but it’s possible to experience allergic rhinitis year-round. Different plants emit their respective pollens at different times of year. Depending on your allergy triggers and where you live, you may experience hay fever in more than one season. You may also react to indoor allergens, such as mold or pet dander.

Symptoms of seasonal allergies

Symptoms of seasonal allergies range from mild to severe. The most common include:

  • sneezing
  • runny or stuffy nose
  • watery and itchy eyes
  • itchy sinuses, throat, or ear canals
  • ear congestion

Less common symptoms include:

  • headache
  • shortness of breath
  • wheezing
  • coughing
Causes of seasonal allergies

Hay fever happens when your immune system identifies an airborne substance that’s usually harmless as dangerous. It responds to that substance, or allergen, by releasing histamines and other chemicals into your bloodstream. Those chemicals produce the symptoms of an allergic reaction.

Diagnosing seasonal allergies

Hay fever is usually easier to diagnose than other allergies. If you have allergic symptoms that only occur at certain times of the year, it’s a sign that you have seasonal allergic rhinitis. Your doctor may also check your ears, nose, and throat to make a diagnosis.

Allergy testing usually isn’t necessary. Your treatment for allergic rhinitis will likely be the same, no matter what type of allergen you react to.

Treating seasonal allergies

The best medicine for hay fever and year-round allergic rhinitis is avoidance. Medications are also available to treat symptoms of hay fever. Some people also try alternative treatments.


Take steps to avoid seasonal allergens. For instance, use an air conditioner with a HEPA filter to cool your home in summer, rather than ceiling fans. Check your local weather network for pollen forecasts, and try to stay indoors when pollen counts are high. At times of year when your hay fever is active:

  • keep your windows shut
  • limit your time outdoors
  • consider wearing a dust mask when you’re outside, especially on windy days


When you can’t avoid your allergens, other treatments are available, including:

  • over-the-counter decongestants and antihistamines, such as cetirizine (Zyrtec) and combinations of acetaminophen, diphenhydramine, and phenylephrine (Benadryl)
  • prescription medications, such as steroid nasal sprays