Treating Environmental Allergies

Allergies sometimes develop when the immune system overreacts to something in the environment. This could be when the body has a negative reaction to something indoors, such as dust, or something outdoors, like pollen.

This reaction is called sensitization. Indoor and outdoor allergens usually do not cause a reaction in most people. But in some people, mold, pollen, dust, dust mites, cockroaches trigger a reaction. Reactions may include:1-3

  • Stuffy or runny nose
  • Itchy or watery eyes
  • Itchy mouth, nose, ears, or throat
  • Hives

The first line of managing environmental allergies is always avoidance. Avoiding what allergens you can helps reduce symptoms. It may also allow you to take less medicine or even no medicine. But when avoidance is not enough, there are many types of drugs to help control your symptoms.1-4

Seasonal versus chronic allergy treatment

Some people have allergies year-round. Others only have them during certain seasons. It is also possible to have both kinds of allergies, where symptoms are year-round but become worse during pollen season.1,2

Seasonal allergies are caused by airborne allergens like mold spores or pollen from grasses, trees, or weeds. People with year-round allergies are typically allergic to things like dust mites, pet dander, cockroaches, and mold.1-3

Whether allergy drugs are taken seasonally or year-round, treatment goals include the ability to work or go to school, sleep through the night, and enjoy normal activities of life.1

Avoidance is the treatment of choice

The primary treatment approach with all environmental allergies is to avoid the allergens triggering symptoms whenever possible. Making some lifestyle and behavioral changes can help you manage exposure. It is also free. Some ways to avoid allergens include:1,3

  • Keep windows closed to keep pollen out
  • Use air conditioning in your home and car instead of opening the windows
  • Wear sunglasses outdoors to protect your eyes from pollen
  • Cover bedding with dust mite covers
  • Use a dehumidifier to reduce mold, mildew, and dust mites
  • Wash your hands to remove allergens
  • Change your clothes as soon as you come indoors to prevent pollen from spreading in the home

Symptom-based treatment

You may still have allergy symptoms after taking steps to avoid or minimize exposure to the allergens that affect you. You may need to take medicines to treat your symptoms. The most common symptoms of respiratory allergies include:2,3

  • Runny nose
  • Stuffy nose due to blockage or congestion
  • Sneezing
  • Itchy eyes, mouth, or skin
  • Fatigue resulting from poor sleep

Allergy drugs

There are many drug choices available to help reduce the symptoms of environmental allergies. They can come in different forms, such as:2,4

  • Pills, capsules, and tablets
  • Liquids
  • Nasal sprays
  • Eye drops
  • Shots

Some are available over-the-counter in your local drug store or supermarket. Others require a prescription. Treatment options include:3,4

  • Antihistamines
  • Decongestants
  • Steroid nasal sprays (corticosteroids)
  • Leukotriene receptor antagonists (LTRAs)
  • Mast cell stabilizers (cromolyn sodium)
  • Allergy shots or sublingual therapy
  • Epinephrine

Antihistamines

Antihistamines are oral and nasal drugs that block the effects of histamines. These are chemicals produced by the body during an allergic reaction. These drugs treat:1-4

  • Runny nose
  • Itchy or watery eyes
  • Hives
  • Swelling
  • Other symptoms

They are less effective for nasal congestion. Some antihistamines may cause drowsiness. The newer antihistamines are less sedating. They come in tablet or capsule form, as well as eye drops and nasal sprays.1-4

Decongestants

Decongestants are oral or nasal medicines used to reduce nasal congestion. They work by constricting blood vessels in the nasal passages. This reduces the swelling that makes your head feel stuffy.2,4

Side effects of oral decongestants include insomnia, irritability, high blood pressure, and heart palpitations.2,4

Prolonged use of decongestant nasal sprays can cause rebound congestion. This is a condition that develops when you use decongestants more than 3 days in a row. It causes worse congestion.2,4

Steroid nasal sprays

Steroid nasal sprays (corticosteroids) treat some kinds of allergies by reducing swelling and inflammation. An oral form can be used for severe symptoms, but the nasal spray is most effective for a stuffy, itchy, runny nose, and sinuses.1

Nosebleeds are a common side effect of nasal sprays.1

Leukotriene receptor antagonists

LTRAs are oral pills used to treat both allergy and asthma symptoms. They work by blocking the action of chemicals in the body called leukotrienes. These chemicals cause allergy symptoms like nasal congestion, runny nose, and sneezing. LTRAs make it easier for people with allergies and asthma to breathe.4

In some people, LTRAs can lead to mood or behavior changes.4

Mast cell stabilizers

Mast cell stabilizers (cromolyn sodium) are a type of drug that help prevent mast cells from responding to specific allergens. These drugs come as pills, eye drops, or nose sprays. The nose spray can be used before exposure to allergens or as a maintenance drug.2,4

Allergy shots

Allergy shots and sublingual therapy are types of immunotherapy. Immunotherapy gradually exposes the body to small amounts of certain allergens to help reduce the body’s allergic response over time.1,4

This is a treatment recommended for those who do not respond well to other treatments, have undesired side effects from drugs, or wish to have more permanent relief from their allergies. This treatment uses shots or medicine under the tongue and can last for a few years. It is the most expensive and time-consuming treatment option, but it can bring long-term relief.1,4

Epinephrine

Epinephrine is an important drug used to treat the most severe type of allergic reaction, anaphylaxis. It comes in an auto-injector device with pre-measured amounts. However, it is rarely needed for environmental allergies.1,2

Things to know

These are not all the possible side effects of allergy drugs. Talk to your doctor about what to expect when taking any allergy medicine. You also should call your doctor if you have any changes that concern you when taking these drugs.

Some drugs or supplements may interfere with each other. This means both drugs may work less well, or you may have serious side effects. Some medicines should also be used with caution in certain health conditions.

Before starting any allergy drug, you should talk to your doctor about all your health conditions, including any prescription and over-the-counter drugs, vitamins, and supplements you take.

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Written by: Linda Minton | Last reviewed: March 2022