Hay fever, also called allergic rhinitis, causes cold-like signs and symptoms, such as a runny nose, itchy eyes, congestion, sneezing and sinus pressure. But unlike a cold, hay fever isn't caused by a virus. Hay fever is caused by an allergic response to outdoor or indoor allergens, such as pollen, dust mites, or tiny flecks of skin and saliva shed by cats, dogs, and other animals with fur or feathers (pet dander).

Besides making you miserable, hay fever can affect your performance at work or school and generally interfere with your life. But you don't have to put up with annoying symptoms. You can learn to avoid triggers and find the right treatment.

Hay fever signs and symptoms can include:

• Runny nose and nasal congestion
• Watery, itchy, red eyes (allergic conjunctivitis)
• Sneezing
• Cough
• Itchy nose, roof of mouth or throat
• Swollen, blue-colored skin under the eyes (allergic shiners)
• Postnasal drip
• Fatigue

Seasonal factors

Your hay fever signs and symptoms may start or worsen at a particular time of year. Triggers include:

• Tree pollen, which is common in early spring.
• Grass pollen, which is common in late spring and summer.
• Ragweed pollen, which is common in fall.
• Dust mites, cockroaches and dander from pets can be bothersome year-round (perennial). Symptoms caused by dander might worsen in winter, when houses are closed up.
• Spores from indoor and outdoor fungi and molds are considered both seasonal and perennial.

Hay fever or common cold?

Signs and symptoms can be similar, so it can be difficult to tell which one you have.

When to see a doctor

See your doctor if:

• You can't find relief from your hay fever symptoms
• Allergy medications don't provide relief or cause annoying side effects
• You have another condition that can worsen hay fever symptoms, such as nasal polyps, asthma or frequent sinus infections

Many people — especially children — get used to hay fever symptoms, so they might not seek treatment until the symptoms become severe. But getting the right treatment might offer relief.

When you have hay fever, your immune system identifies a harmless airborne substance as harmful. Your immune system then produces antibodies to this harmless substance. The next time you come in contact with the substance, these antibodies signal your immune system to release chemicals such as histamine into your bloodstream, which cause a reaction that leads to the signs and symptoms of hay fever.

The following can increase your risk of developing hay fever:

• Having other allergies or asthma
• Having atopic dermatitis (eczema)
• Having a blood relative (such as a parent or sibling) with allergies or asthma
• Living or working in an environment that constantly exposes you to allergens — such as animal dander or dust mites
• Having a mother who smoked during your first year of life

Problems that may be associated with hay fever include:

• Reduced quality of life. Hay fever can interfere with your enjoyment of activities and cause you to be less productive. For many people, hay fever symptoms lead to absences from work or school.
• Poor sleep. Hay fever symptoms can keep you awake or make it hard to stay asleep, which can lead to fatigue and a general feeling of being unwell (malaise).
• Worsening asthma. Hay fever can worsen signs and symptoms of asthma, such as coughing and wheezing.
• Sinusitis. Prolonged sinus congestion due to hay fever may increase your susceptibility to sinusitis — an infection or inflammation of the membrane that lines the sinuses.
• Ear infection. In children, hay fever often is a factor in middle ear infection (otitis media).

There's no way to avoid getting hay fever. If you have hay fever, the best thing to do is to lessen your exposure to the allergens that cause your symptoms. Take allergy medications before you're exposed to allergens, as directed by your doctor.

Your doctor will perform a physical examination, take a medical history, and possibly recommend one or both of the following tests:

• Skin prick test. You're watched for an allergic reaction after small amounts of material that can trigger allergies are pricked into the skin of your arm or upper back. If you're allergic, you develop a raised bump (hive) at the site of that allergen. Allergy specialists usually are best equipped to perform allergy skin tests.
• Allergy blood test. A blood sample is sent to a lab to measure your immune system's response to a specific allergen. Also called the radioallergosorbent test (RAST), this test measures the amount of allergy-causing antibodies in your bloodstream, known as immunoglobulin E (IgE) antibodies.

It's best to limit your exposure to substances that cause your hay fever as much as possible. If your hay fever isn't too severe, over-the-counter medications may be enough to relieve symptoms. For worse symptoms, you may need prescription medications.

Many people get the best relief from a combination of allergy medications. You might need to try a few before you find what works best.

If your child has hay fever, talk with your doctor about treatment. Not all medications are approved for use in children. Read labels carefully.

Medications for hay fever include:

• Nasal corticosteroids. These prescription nasal sprays help prevent and treat the nasal inflammation, nasal itching and runny nose caused by hay fever. For many people they're the most effective hay fever medications, and they're often the first type of medication prescribed.

  Examples include mometasone (Nasonex) and budesonide (Rhinocort), both available by prescription, and Fluticasone (Flonase Allergy Relief), budesonide (Rhinocort Allergy) and triamcinolone (Nasacort Allergy 24 Hour), available over the counter. The prescription nasal spray azelastine and fluticasone (Dymista) combines an antihistamine with a steroid.

  Nasal corticosteroids are a safe, long-term treatment for most people. Side effects can include an unpleasant smell or taste and nose irritation. Steroid side effects are rare.

• Antihistamines. These preparations are usually given as pills. However, there are also antihistamine nasal sprays and eyedrops. Antihistamines can help with itching, sneezing and a runny nose but have less effect on congestion. They work by blocking a symptom-causing chemical released by your immune system during an allergic reaction (histamine).

  Over-the-counter pills include loratadine (Claritin, Alavert), cetirizine (Zyrtec Allergy) and fexofenadine (Allegra Allergy). The prescription antihistamine nasal sprays azelastine (Astelin, Astepro) and olopatadine (Patanase) can relieve nasal symptoms. Antihistamine eyedrops such as ketotifen fumarate (Alaway) help relieve eye itchiness and eye irritation caused by hay fever.

• Decongestants. These medications are available in over-the-counter and prescription liquids, tablets and nasal sprays. Over-the-counter oral decongestants include pseudoephedrine (Sudafed, Afrinol, others). Nasal sprays include phenylephrine hydrochloride (Neo-Synephrine) and oxymetazoline (Afrin).

  Oral decongestants can cause a number of side effects, including increased blood pressure, insomnia, irritability and headache. Don't use a decongestant nasal spray for more than two or three days at a time because it can actually worsen symptoms when used continuously (rebound congestion).

• Cromolyn sodium. This is available as an over-the-counter nasal spray that must be used several times a day. It's also available in eye-drop form with a prescription. It helps relieve hay fever symptoms by preventing the release of histamine. Most effective when you start using it before you have symptoms, cromolyn sodium doesn't have serious side effects.

• Leukotriene modifier. Montelukast (Singulair) is a prescription tablet taken to block the action of leukotrienes — immune system chemicals that cause allergy symptoms such as excess mucus production. It's especially effective in treating allergy-induced asthma. It's often used when nasal sprays can't be tolerated or for mild asthma.

  Montelukast can cause headaches. In rare cases, it has been linked to psychological reactions such as agitation, aggression, hallucinations, depression and suicidal thinking. Seek medical advice right away for any unusual psychological reaction.

• Nasal ipratropium. Available in a prescription nasal spray, ipratropium helps relieve severe runny nose by preventing the glands in your nose from producing excess fluid. It's not effective for treating congestion, sneezing or postnasal drip.

  Mild side effects include nasal dryness, nosebleeds and sore throat. Rarely, it can cause more-severe side effects, such as blurred vision, dizziness and difficult urination. The drug is not recommended for people with glaucoma or men with an enlarged prostate.

• Oral corticosteroids. Corticosteroid pills such as prednisone sometimes are used to relieve severe allergy symptoms. Because the long-term use of corticosteroids can cause serious side effects such as cataracts, osteoporosis and muscle weakness, they're usually prescribed for only short periods of time.

Other treatments for hay fever include:

• Allergy shots (immunotherapy). If medications don't relieve your hay fever symptoms or cause too many side effects, your doctor may recommend allergy shots (immunotherapy or desensitization therapy). Over three to five years, you'll receive regular injections containing tiny amounts of allergens. The goal is to get your body used to the allergens that cause your symptoms, and decrease your need for medications.

  Immunotherapy might be especially effective if you're allergic to cat dander, dust mites, or pollen produced by trees, grass or weeds. In children, immunotherapy may help prevent the development of asthma.

• Under-the-tongue (sublingual) allergy tablets. Rather than getting shots, you have tiny amounts of allergen in pill form dissolve in your mouth, usually daily.

• Rinsing your sinuses. Rinsing your nasal passages with distilled, sterile saline (nasal irrigation) is a quick, inexpensive and effective way to relieve nasal congestion. Rinsing flushes out mucus and allergens from your nose.

  Look for a squeeze bottle or a neti pot — a small container with a spout designed for nose rinsing — at your pharmacy or health food store. To make up the saline irrigation solution, use water that's distilled, sterile, previously boiled and cooled, or filtered using a filter with an absolute pore size of 1 micron or smaller. Also be sure to rinse the irrigation device after each use with similarly distilled, sterile, previously boiled and cooled, or filtered water and leave open to air-dry.

It's not possible to avoid allergens completely, but you can reduce your symptoms by limiting your exposure to them. If you know what you're allergic to, you can avoid your triggers.

Pollen or molds

• Close doors and windows during pollen season.
• Don't hang laundry outside — pollen can stick to sheets and towels.
• Use air conditioning in your house and car.
• Use an allergy-grade filter in your home ventilation system and change it regularly.
• Avoid outdoor activity in the early morning, when pollen counts are highest.
• Stay indoors on dry, windy days.
• Use a dehumidifier to reduce indoor humidity.
• Use a high-efficiency particulate air (HEPA) filter in your bedroom and other rooms where you spend a lot of time.
• Avoid mowing the lawn or raking leaves.
• Wear a dust mask when cleaning house or gardening.

Dust mites

• Use allergy-proof covers on mattresses, box springs and pillows.
• Wash sheets and blankets in water heated to at least 130 F (54 C).
• Use a dehumidifier or air conditioner to reduce indoor humidity.
• Vacuum carpets weekly with a vacuum cleaner equipped with a small-particle or HEPA filter.
• Spray insecticide designed to kill dust mites (acaricides) and approved for indoor use on carpets, furniture and bedding.
• Consider removing carpeting, especially where you sleep, if you're highly sensitive to dust mites.

Cockroaches

• Block cracks and crevices where roaches can enter.
• Fix leaky faucets and pipes.
• Wash dishes and empty garbage daily.
• Sweep food crumbs from counters and floors.
• Store food, including pet food, in sealed containers.
• Consider professional pest extermination.

Pet dander

• Keep pets out of your home, if possible.
• Bathe dogs twice a week, if possible. The benefit of bathing cats hasn't been proved. Keep pets out of your bedroom and off furniture.

While there isn't much evidence about how well alternative treatments work, a number of people try them for hay fever. These include:

• Herbal remedies and supplements. Extracts of the shrub butterbur may help prevent seasonal allergy symptoms. If you try butterbur, be sure to use a product that's labeled "PA-free," which indicates that it's had potentially toxic substances removed.

  There's some limited evidence that spirulina and Tinospora cordifolia also may be effective. Though their benefits are unclear, other herbal remedies for seasonal allergies include capsicum, honey, vitamin C and fish oil.

• Acupuncture. Some people claim that acupuncture can help with seasonal allergy symptoms. There's limited evidence that these treatments work, but there's also little evidence of harm.

You're likely to start by seeing your family doctor or a primary care provider. However, in some cases when you call to set up an appointment, you may be referred to an allergist or other specialist.

Here's some information to help you prepare for your appointment:

• Write down your symptoms, when they occur and what seems to trigger them. Include symptoms that might seem unrelated to hay fever.
• Write down recent life changes, such as a move to a new home or new part of the country.
• List medications, vitamins and supplements you take.
• Take a family member or friend along, if possible. Someone who accompanies you can help you remember information from your doctor.
• Write down questions for your doctor.

For hay fever, some questions to ask include:

• What is likely causing my symptoms?
• What tests do I need?
• Is my condition likely to go away on its own?
• What is the best course of action?
• What other approaches can you suggest?
• I have other health conditions. How can I best manage them together?
• Are there restrictions I should follow?
• Should I see a specialist?
• Are there brochures or other printed material that I can have? What websites do you recommend?

Don't hesitate to ask other questions you have.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

• When did your symptoms begin?
• Have your symptoms been continuous or occasional?
• How severe are your symptoms?
• What seems to trigger your symptoms?
• What, if anything, seems to improve your symptoms?
• Do any of your closest relatives (such as a parent or sibling) have hay fever or other allergies?
• Do your symptoms interfere with work, school or sleep?

What you can do in the meantime

If you don't see your doctor right away, over-the-counter remedies may help ease symptoms. A number of medications are available that may help relieve your hay fever symptoms. They include pills, liquids, nasal sprays and eye-drops.