Definition:

Allergy refers to a variety of biochemical reactions that may result in specific physical symptoms, such as runny nose, sneezing, wheezing, bronchoconstriction, and even life-threatening anaphylaxis.

• It is estimated that more than half of US citizens test positive for one or more allergens and more than 20% of U.S. citizens suffer from an allergic condition.
• There seems to be a genetic predisposition to developing allergies, also referred to as atopy.
• There are three stages to the allergic response: In the first stage, the immune system encounters the foreign substance and identifies it as an invader. It then primes the immune system to recognize this invader as an enemy that needs to be destroyed in future encounters. This stage is known as sensitization. The subsequent stages are mast cell activation and prolonged immune activation.

Treatment:

Environment/Nutrition:

• Breast-feed babies for at least the first year. 
• Feeding children eggs and peanuts between the ages of four and six months may reduce the risk of developing food allergies to these foods later in life.
• Reduce indoor allergens such as dust mite allergens (by mattress and pillow encasements, removal of carpeting as possible, replacement of curtains with shades), and removal of allergenic pets from the home (or at least the bedroom).
• Wash bedclothes weekly in hot water.
• Use a high-efficiency particulate air (HEPA) filter (or at least a portable one in the bedroom)
• Use air filters with a rating of MERV13 or higher
• Regularly  vacuum carpeted areas
•  Plan activities to avoid exposure to early morning peak pollen counts.
• Diagnose and eliminate food allergies

• Decrease dairy (milk protein) and total protein intake. Plant proteins are preferable.
• Consume omega-3–rich fats found in cold-water fish, nuts, greens, and ground flaxseed.  
• Increase water intake dramatically to maintain adequate hydration.
• Increase your intake of olive oil as well as natural bioflavonoids and antioxidants by eating more organic fruits (especially berries) and vegetables.
• Avoid processed foods, partially hydrogenated oils, vegetable oils, white sugar, and flour.

Mind-Body Therapy:

• Clinical hypnosis may markedly attenuate allergic reactivity.

Immunotherapy:

• This is typically reserved for those patients with more severe or refractory symptoms, life-threatening allergic reactivity, or coexisting conditions (e.g., asthma, sinusitis).
• Consider sublingual immunotherapy before subcutaneous immunotherapy.

Pharmaceuticals and supplements when used appropriately can help reduce the symptoms of allergies.

A trial of homeopathy may be useful in individuals with multiple chemical or drug sensitivities.