Avoiding allergens Dr Adrian Morris There are plenty of steps you can take to cut down on allergens in your home.

In this article

Basic rules

House dust mites

Pets in the home

Take the following immediate actions to cut down on allergens in your home:

• Keep your home dry and well ventilated
• Open windows for at least one hour, twice a day and keep vents open, particularly in kitchens and bathrooms
• However, if you get hay fever keep the windows closed as much as possible during the peak of the pollen season
• Don't dry clothes indoors, especially in your bedroom or living room
• If you have central heating, turn it down by a few degrees
• Increase the ventilation if your home is very humid - a dehumidifier might help

It's the mites' droppings that cause allergies

Household dust is a great breeding ground for microscopic house dust mites, which like indoor environments and feed on old human skin flakes. It's the mites' droppings that cause allergies. Eradication measures should focus on the bedroom, as that's where we spend a lot of time asleep in bed - with the house dust mites.

There are various ways to keep a lid on house dust mites:

• Choose wooden or other hard vinyl floorings instead of thick carpets, and fit roller blinds, which can be wiped clean, rather than draped curtains
• Remove cushions, soft toys and other upholstered furniture
• Avoid indoor houseplants, as they are dust traps
• Don't use woollen blankets or feather bedding in your home, try synthetic pillows and acrylic duvets instead
• If you can afford it, buy a high-filtration vacuum cleaner with a HEPA filter. Most standard cleaners stir up dust as you clean and release most of the dust back into the air
• Always wipe surfaces with a clean, damp cloth, as dry dusting will spread the allergens further

The most beneficial action you can take is to buy Allergy UK-approved barrier covers for your bedding. These are designed to prevent house dust mites and their tiny droppings escaping from your pillows, mattresses and duvets. They are made from a soft microporous material, which is comfortable to sleep on.

Allergy UK has more information on mite-resistant covers and vacuum cleaners.

Wash your sheets, duvet covers and pillowcases once a week in a hot wash (60°C), then iron your sheets and bedclothes with a hot iron, which will help to kill mites.

Your child may be unhappy about giving up soft toys. You can kill dust mites by machine washing toys once a fortnight and then placing them in the freezer overnight, after which they should be thoroughly tumble-dried.

Acarosides - chemicals that kill house dust mites - are expensive and only offer temporary benefit. The dead mites still have to be removed from carpets and furnishings by intensive vacuuming.

Pet allergies are triggered by exposure to their dead skin flakes (dander), as well as proteins in their saliva and dried urine

It's a common misconception that animal fur causes allergies. In fact, pet allergies are triggered by exposure to their dead skin flakes (dander), as well as proteins in their saliva and dried urine.

With pet allergies, it's practical to remove the pet permanently from the home. If this proves too traumatic, try the following:

• Keep pets outside as much as possible or limit them to one room only, preferably one without carpeting
• Don't allow pets into bedrooms, as skin flakes (dander) can remain airborne for long periods. Cat dander allergen can also be carried around on clothing into schools or the workplace
• Try to wash pets regularly - fortnightly if possible
• Female animals produce less allergen and castration will reduce the production of allergen by male cats and dogs

If you're allergic to cats and are visiting the home of a cat owner, ask them not to dust, sweep or vacuum on the day you arrive. Disturbing the dust could make your allergy worse as stirred-up cat allergen can remain in the air for over 24 hours.

You should consider taking antihistamine medication one hour before entering a cat-inhabited home. This will reduce symptoms more than taking medication after exposure.

This article was last medically reviewed by Dr Adrian Morris in September 2007.
First published in September 1999.