Pollen is the dusty powder that plants release to reproduce. The types of plants that cause pollen allergies include grass, weeds and trees. When you get allergy symptoms it's called allergic rhinitis, also known as hay fever. Pollen allergy symptoms may include nasal allergies, a cough and sometimes difficulty breathing (chest tightness).

Outdoors you’ll find pollen everywhere. It’s been recorded 400 miles out at sea and two miles high in the atmosphere. Plants release millions of the tiny grains daily. Now climate change is lengthening the season for some species and making their pollen more allergenic. And pollen levels are rising in cities because of pollution.

A misconception about pet allergies is that you’re allergic to animal hair. It’s actually the allergens trapped in fur and feathers. Pets also shed tiny particles of dead skin, a bit like dandruff. This pet dander can cause allergic reactions. The proteins in saliva, sebum and urine can be responsible too.

The most common pets behind animal allergies include cats and dogs. But many other animals can cause them too. Anything producing dander is a possible trigger, regardless of whether it has fur or feathers. Allergic symptoms tend to affect the nose and eyes.

Dust mites live in our homes and indoor public places. They thrive where it’s warm and humid and are commonly found on mattresses, pillows and bed linen and in carpets. Dust mites are different from bed bugs in that they don’t bite. Instead they like to snack on our shed skin. They’re also microscopic.

Dust mite allergy is an allergic reaction to their feces and dead skin. Dust mites produce roughly 200 times their weight in waste over the course of their lifetime. These particles are roughly the same size as a pollen grain. So they’re easy to breathe in without realizing. One of the main symptoms of dust mite allergy is a stuffy nose.

Mold is a fungus that breaks down dead organic matter indoors and outside. Microscopic spores float through the air as part of mold’s fertilization process. But they can also end up in your nose.

Around 100 types cause mold allergy. You might get cold-like symptoms, eye allergies, skin reactions or breathing difficulties. Occasionally mold can trigger serious allergic conditions in people exposed to high levels of the allergen at work.

Some people are allergic to insect stings like those from a bee or wasp. A local reaction to the venom may spread beyond the normal wheal or raised bump. For instance your whole arm could be swollen and red, possibly for a few days.

An insect sting allergy can also affect your whole body. This serious reaction can be life-threatening and should be treated as a medical emergency.

It’s possible to be allergic to anything edible. The most common food allergies include peanuts and tree nuts, sesame seeds, cow’s milk, eggs, fish, shellfish and soybeans. You can develop a food allergy at any age but younger children tend to be most affected.

Symptoms range from mild to very severe and may include tingling in your mouth or throat or an itchy rash (hives). Food allergies are different from food intolerances. The first involves your immune system and can be life threatening. The second is difficulty digesting certain foods.

Latex is a natural protein from the sap of the rubber tree. It’s made into things like balloons, rubber gloves, condoms and sneakers.

Some people get allergic reactions when they come into contact with latex. It can cause swelling, itching and skin redness. Also respiratory symptoms if you breathe in particles of latex. Latex allergy can occasionally trigger a severe allergic reaction (anaphylaxis). It should be treated as a medical emergency.

Many reactions to medication are not because of a true drug allergy but may be known side effects. Drug allergies are relatively uncommon; penicillin is probably the best known. They involve your immune system in the same way the other allergy types do. The difference is that even a mild allergic reaction to drugs affects your whole body. You may get hives or even anaphylaxis. The latter is an emergency and you should seek immediate medical attention.

Pollen is the dusty powder that plants release to reproduce. The types of plants that cause pollen allergies include grass, weeds and trees. When you get allergy symptoms it's called allergic rhinitis, also known as hay fever. Pollen allergy symptoms may include nasal allergies, a cough and sometimes difficulty breathing (chest tightness).

A misconception about pet allergies is that you’re allergic to animal hair. It’s actually the allergens trapped in fur and feathers. Pets also shed tiny particles of dead skin, a bit like dandruff. This pet dander can cause allergic reactions. The proteins in saliva, sebum and urine can be responsible too.

Dust mites live in our homes and indoor public places. They thrive where it’s warm and humid and are commonly found on mattresses, pillows and bed linen and in carpets. Dust mites are different from bed bugs in that they don’t bite. Instead they like to snack on our shed skin. They’re also microscopic.

Some people are allergic to insect stings like those from a bee or wasp. A local reaction to the venom may spread beyond the normal wheal or raised bump. For instance your whole arm could be swollen and red, possibly for a few days.

An insect sting allergy can also affect your whole body.

Latex is a natural protein from the sap of the rubber tree. It’s made into things like balloons, rubber gloves, condoms and sneakers.

Some people get allergic reactions when they come into contact with latex. It can cause swelling, itching and skin redness.