What are allergy tests
Patch tests are used to investigate a type of eczema known as contact dermatitis, which can be caused by your skin being exposed to an allergen.
A little quantity of the suspected allergen is added to special metal discs, which are then taped to your skin for 48 hours and monitored for a reaction.
Blood tests may be used instead of, or alongside, skin prick tests to assist diagnose common allergies.
A sample of your blood is removed and analysed for specific antibodies produced by your immune system in response to an allergen.
Allergy testing kits
The use of commercial allergy-testing kits isn’t recommended.
These tests are often of a lower standard than those provided by the NHS or accredited private clinics, and are generally considered to be unreliable.
Allergy tests should be interpreted by a qualified professional who has detailed knowledge of your symptoms and medical history.
Sheet final reviewed: 22 November 2018
Next review due: 22 November 2021
Itchy eyes, a congested nose, sneezing, wheezing and hives: these are symptoms of an allergic reaction caused when plants release pollen into the air, generally in the spring or drop. Numerous people use hay fever as a colloquial term for these seasonal allergies and the inflammation of the nose and airways.
But hay fever is a misnomer, said Dr.
Jordan Josephson, an ear, nose and throat doctor and sinus specialist at Lenox Hill Hospital in New York City.
«It is not an allergy to hay,» Josephson, author of the book «Sinus Relief Now» (Perigee Trade, 2006), told Live Science.
«Rather, it is an allergy to weeds that pollinate.»
Doctors and researchers prefer the phrase allergic rhinitis to describe the condition. More than 50 million people experience some type of allergy each year, according to the Asthma and Allergy Foundation of America. In 2017, 8.1% of adults and 7.7% of children reported own allergic rhinitis symptoms, according to the Centers for Disease Control and Prevention (CDC).
Worldwide, between 10 and 30% of people are affected by allergic rhinitis, Josephson said.
In 2019, spring arrived early in some parts of the country and later in others, according to the National Phenology Network (NPN). Spring brings blooming plants and, for some, lots of sneezing, itchy, watery eyes and runny noses.
According to NPN data, spring reared its head about two weeks early in areas of California, Nevada and numerous of the Southern and Southeastern states. Much of California, for example, is preparing for a brutal allergy season due to the large quantity of winter rain. On the other hand, spring ranged from about one to two weeks tardy in the Northwest, the Midwest and the Mid-Atlantic U.S. [Watch a Massive ‘Pollen Cloud’ Explode from Late-Blooming Tree]
In a few cases, a test called a food challenge may also be used to diagnose a food allergy.
During the test, you’re given the food you ponder you’re allergic to in gradually increasing amounts to see how you react under shut supervision.
This test is riskier than other forms of testing, as it could cause a severe reaction, but is the most precise way to diagnose food allergies.
And challenge testing is always carried out in a clinic where a severe reaction can be treated if it does develop.
The symptoms of allergic rhinitis may at first feel love those of a freezing. But unlike a freezing that may incubate before causing discomfort, symptoms of allergies generally appear almost as soon as a person encounters an allergen, such as pollen or mold.
Symptoms include itchy eyes, ears, nose or throat, sneezing, irritability, nasal congestion and hoarseness.
People may also experience cough, postnasal drip, sinus pressure or headaches, decreased sense of smell, snoring, sleep apnea, fatigue and asthma, Josephson said. [Oral Allergy Syndrome: 6 Ways to Avoid an Itchy, Tingling Mouth]
Many of these symptoms are the immune system’s overreaction as it attempts to protect the vital and sensitive respiratory system from exterior invaders.
The antibodies produced by the body hold the foreign invaders out, but also cause the symptoms characteristic of allergic responses.
People can develop hay fever at any age, but most people are diagnosed with the disorder in childhood or early adulthood, according to the Mayo Clinic. Symptoms typically become less severe as people age.
Often, children may first experience food allergies and eczema, or itchy skin, before developing hay fever, Josephson said. «This then worsens over the years, and patients then develop allergies to indoor allergens love dust and animals, or seasonal rhinitis, love ragweed, grass pollen, molds and tree pollen.»
Hay fever can also lead to other medical conditions.
People who are allergic to weeds are more likely to get other allergies and develop asthma as they age, Josephson said. But those who get immunotherapy, such as allergy shots that assist people’s bodies get used to allergens, are less likely to develop asthma, he said.
If you own a suspected food allergy, you may be advised to avoid eating a specific food to see if your symptoms improve.
After a few weeks, you may then be asked to eat the food again to check if you own another reaction.
Do not attempt to do this yourself without discussing it with a qualified healthcare professional.
Skin prick testing
Skin prick testing is one of the most common allergy tests.
It involves putting a drop of liquid onto your forearm that contains a substance you may be allergic to.
The skin under the drop is then gently pricked.
If you’re allergic to the substance, an itchy, red bump will appear within 15 minutes.
Most people discover skin prick testing not particularly painful, but it can be a little uncomfortable.
It’s also extremely safe.
Make certain you do not take antihistamines before the test, as they can interfere with the results.