Hawaii Allergy Season: Peak, Timing, and Symptoms

Written by Drew Wood
Updated: April 20, 2023
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Who doesn’t love Hawaii? Sunny tropical beaches, waterfalls, lush rainforests, and flowers all year round. It really does meet the definition of “paradise.” But for people who suffer from allergies, a visit to Hawaii can be miserable, with red itchy eyes, coughing, and congestion. Not a very romantic look, that’s for sure. With some preparation, though, you can consider what allergens are most problematic at different times of year and take the precautions you need to in order to get the most from your time in heaven-on-earth.

All About Allergies

Before talking specifically about Hawaii’s allergy season, here’s an overview of what causes allergies to help you start thinking about prevention options:

What Causes Allergies?

A person with allergies has an immune system that is sensitive to one or more allergens, or allergy-causing substances. These can include chemicals, foods, bee stings, pet dander, mold, dust mites or pollen from trees, grasses, and weeds. When exposed to an allergen the body over-reacts, releasing chemicals like histamine that result in familiar symptoms such as red and itchy eyes, rashes or hives, coughing, runny nose, and congestion. Pets can also suffer from allergies, with mammalian pets often sharing the same allergens as humans. In fact, dogs can even be allergic to cats!

Woman with allergy symptoms

In Hawaii many different allergens like pollen, mold, dust mites, foods, or insect stings may set off your immune system.


How Can You Know if You have an Allergy?

Having classic allergy symptoms such as nasal congestion and post-nasal drip, red itchy eyes, hives, or rashes, a constricted feeling in the throat and coughing can be indications you have an allergy, especially if you can connect it with a particular environment or activity. For example, if you notice those symptoms when you change the bed sheets, it’s possible you have a dust mite allergy. If it bothers you to feed Timothy hay to your daughter’s guinea pig, you might be allergic to either the hay or pet dander, or both.

However, allergy-like symptoms can also result from other conditions, such as colds or the flu, hormonal changes, stress and anxiety or even structural problems in the bones and tissues of your nose and sinus cavities. When a person has allergy symptoms without a known cause, it is called non-allergenic rhinitis and the symptoms are treated with regular allergy medications.

The only way to know for sure if you have an allergy, and what you are allergic to, is to see an allergist for testing. They may do a skin test on you which involves putting small amounts of typical allergens on your skin and pricking the skin with a needle to see if a red welt develops on any of them. Alternately, some skin tests involve covering the allergen with a patch for 48 hours to wait for a reaction. Another possibility is to have a blood test to determine whether your body has produced antibodies against allergens.

Allergy Test

An allergist may test you for common allergens by putting a small amount of concentrate on your skin and looking for a reaction.


How Can You Avoid Allergens?

The best way to manage allergies is to avoid allergens as much as possible – a difficult feat as potential allergens are all around us, indoors and outdoors. Here are some ideas:

  • Remove identifiable sources of allergies from your home and yard. It may be time to landscape.
  • Keep your house as clean and dust-free as possible. Use electrostatic cloths, HEPA air filters, and replace your furnace and air conditioning filters regularly.
  • Keep your windows closed and use your air conditioning to filter the air.
  • Pay attention to the daily pollen count on your local news or with an online app. Adjust your plans for outdoor activities on high pollen days.
  • Wash your clothes and shower after time outdoors on high pollen days to prevent spreading allergens around your house.
  • Wash bedding regularly in hot water to kill dust mites.
  • Wear a mask when you go outdoors at times when your allergies are especially bad.
  • When considering a pet, look for one that is hypoallergenic. If your current pet aggravates your allergies you may have to make the tough decision to rehome them.
  • In the very worst case scenarios, you can research other parts of the country as potential places to live that are less problematic for you.
Allergy Season

On heavy pollen days, people with allergies may choose to modify their outdoor activity plans.

©Chad Robertson Media/Shutterstock.com

What are the Treatment Options for Allergies?

Allergy symptoms can be treated at home with over-the-counter medications such as decongestants and antihistamines, and nasal sprays and rinses. At the end of this article we’ll provide you with a list of options for generic meds with the same active ingredients as four of the most popular name-brand allergy medicines.

In more severe cases, your allergist might recommend immunotherapy, in which you will periodically receive injections of small amounts of allergens to help your immune system develop antibodies and not over-react when exposed to an allergen. These can be very effective but the process can take a year or more and can be expensive if not covered by insurance.

Cycling, Mountain Biking, Mountain Bike, Bicycle, Sunset

Knowing how to manage your allergies can help you better enjoy all the outdoor activities Hawaii has to offer.


What if You Don’t Treat Your Allergies?

Allergies in some people go away on their own, such as when children might outgrow a food allergy, but in other people they may become worse and new allergies may develop. Mild allergies can be just an annoyance that many people choose to live with or treat with over-the-counter medications on an as-needed basis. If they persist, though, they can cause sleep disturbances and irritability and develop into sinusitis, an inflammatory condition that can create breathing problems and debilitating facial pain and headaches. In the worst case scenario, severely allergic people may react to an allergen with anaphylaxis, a life-threatening constriction of their breathing passages along with a dangerous drop in blood pressure. A person going into anaphylactic shock must be injected with an epi-pen immediately and emergency services should be called at once.


Treating mild allergies with over-the-counter medications can be a good option, but when allergies are severe, they can be life-threatening.


When is Allergy Season in Hawaii?

Now that you’ve had a primer on allergies, what can you expect at different times of year as a resident or visitor to Hawaii? Hawaii is a volcanic island chain that maintains a constantly warm temperature all year long because of the trade winds. The islands have incredibly diverse microclimates and biomes. You’ll find rainforests, deciduous forests, savannas, wetlands and even deserts. Some of the flora and fauna there are unique in all the world.

The main allergens in Hawaii are tree, grass, and weed pollens, mold and dust mites. Additionally, volcanic smoke and ash can produce allergy symptoms but eruptions are unpredictable in their timing and severity.

  • Tree pollen peaks in April and May. Common allergens include koa, kukui, and hau.
  • Grass pollen season is most intense in June and July. Bermuda grass, Johnson grass and Paspalum may bother you at those times.
  • Weed pollinates in August and September. Problematic species include ragweed, pigweed, and sagebrush.
  • Mold is present all year but a bit worse in fall and winter.
  • Dust mites thrive indoors year round.

Allergy season in Hawaii varies from island to island and from day to day in response to atmospheric and ecological conditions. It’s not an exact science, but what we’ve provided here will give you a general idea of what to expect.

Allergy sufferer

You can enjoy Hawaii more if you know when the allergens that bother you are in season.


Your Pet Can Have Allergies Too!

Pets, especially mammals, are subject to some of the same allergies as people. Let’s look at what pets can be allergic to, how they manifest symptoms, and how they can be treated.

Common Allergies of Pets

Some of the most common types of allergies in pets include food allergies, environmental allergies, and flea allergy dermatitis. Some pets have allergic reactions to certain food ingredients, including the type of protein used or certain additives. Others may be allergic to pollens, molds, dust mites, and other environmental things. Flea allergies are very common, resulting from flea bites and causing intense itching, biting, and licking of the skin. Left untreated, your pet can develop a nasty and painful skin infection.

dust mite

Dust mites are a common source of allergies for pets and people. You can help combat them by regularly washing and drying your bedding.


Allergy Symptoms in Pets

Pets of different species and with different allergies may manifest allergy symptoms in different ways. Some things to watch for in cats and dogs are itching, scratching, biting, or licking the skin. The intensity and persistence of this activity contributes to hair loss and irritated skin. You may start to see bald patches on your animal. Pets may also have respiratory symptoms similar to people. Look for discharges from the nose or eyes and coughing, wheezing or other difficulty breathing. Pets may sound like they are choking and cough up liquid. Notice the color of it to help your doctor with a diagnosis. Your vet will be able to recommend medications, environmental or dietary changes, and possible immunotherapy.

Cat licking its paws

Excessive grooming, sometimes leading to bald patches, is one way your pet tells you they have allergies.

©Fayzulin Serg/Shutterstock.com

Can Pets Take Human Allergy Medicine?

Dogs and cats can take some human allergy medicines, but not all. Some that are ok for dogs may be toxic to cats, and vice versa. Moreover, the dosage and timing of the medicine must be adjusted to the weight of your pet to prevent an overdose. Never give your pet human medication without first consulting with a veterinarian. After treating your pet, watch them closely for signs of a reaction to the medication or an interaction with any other medication they may be already taking.

spay a dog at petsmart

Your vet can diagnose and suggest a good treatment plan for your pet’s allergies.


Best Over-The-Counter Allergy Treatments

If you’ve fought with allergies for a while you probably already have some favorite over-the-counter brand names that you know have been effective for you in the past. You could save some money by buying generic versions, though. Below are four examples with the same active ingredients of four of the most popular and effective allergy drugs. Compare with your favorites and see how much you could save.

Amazon Basic Care Loratadine Antihistamine
  • Long-lasting relief from allergy symptoms
  • Non-drowsy formula
  • Active ingredient is the antihistamine Loratadine (10 mg)
  • 24-hour allergy relief
Check Amazon
ValuMeds 24-Hour Allergy Medicine
  • 24-hour allergy relief
  • Works for pollen, hay fever, dry eyes, itchy eyes
  • Main ingredient is Cetirizine HCl
Check Amazon
ValuMeds Antihistamine, Diphenhydramine HCl 25 mg
  • 600 tablets
  • Active ingredient: Diphenhydramine HCl 25 mg
  • Suitable for Children and Adults
  • Relieves Itchy Eyes, Runny Nose, Sneezing

Check Amazon
HealthCareAisle Allergy Relief - Fexofenadine Hydrochloride
  • Active ingredient: Fexofenadine Hydrochloride
  • 90 tablets of 180 mg
  • Non-Drowsy
  • 24-Hour Allergy Relief

Check Amazon

Before self-treating for allergies, be sure to talk to a medical professional to make sure any OTC meds will not interact negatively with other medications you may be taking.

The photo featured at the top of this post is © iStock.com/danielvfung

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About the Author

Drew Wood is a writer at A-Z Animals where his primary focus is on mammals, dinosaurs, and geography. Drew has worked in research and writing for over 20 years and holds a Doctorate in Religion, which he earned in 2009. A resident of Nebraska, Drew enjoys Brazilian jiu-jitsu, reading, and caring for his four dogs.

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