Peanut Allergy

Peanut allergy is a very common form of food allergy in which the body launches an allergic reaction to peanut or peanut-containing foods. Symptoms may range from mild to severe anaphylactic reactions. Most of the symptoms of peanut allergy occur within 20 minutes of exposure to peanuts. 

It is one of the leading cause of anaphylaxis in food allergy. Since peanuts are very common ingredients in foods, complete avoidance is very hard. 

The prevalence of this food allergy has increased over the past few years. People with other forms of food allergy have higher chance of developing allergy to nuts like peanut and tree nut.

Most common symptoms of peanut allergy are: 

• Itchy skin or skin rashes 
• Itching around the mouth and throat
• Nausea or vomiting
• Abdominal cramps 
• Diarrhea
• Congestion in nose
• Shortness of breath
• Wheezing

Exposure to peanut may cause severe symptoms, or anaphylaxis, in some people. This is a medical emergency characterized by: 

• Shortness of breath
• Constriction of airways
• Drop in blood pressure
• Increased pulse rate
• Lightheadedness 
• Loss of consciousness

Peanut allergy is caused by an exaggerated response of the immune system to peanuts and peanut-containing food. When body is exposed to peanut, the immune system overreacts and produces antibodies against these allergens. 

On further exposure to peanuts, antibodies activate the production of histamines. Histamines are chemicals responsible for the development of typical allergy symptoms. 

Eating peanuts or peanut-containing food is the most common cause of allergic reaction. Some foods do not contain peanuts as such, but may be exposed to these nuts during processing. This cross-contact also result in allergy symptoms in people who are sensitive to nuts. 

Inhaling airborne particles as in peanut flour or peanut oil also triggers an immune reaction.

People having a family history of peanut allergy, or have other food allergies have an increased risk of developing peanut allergy. Atopic dermatitis and age are also risk factors of this allergy. Peanut allergy is most common among children. 

Symptoms and physical examination are the two methods for confirmatory diagnosis of peanut allergy. Symptoms usually appear within few minutes of exposure to the allergen. 

• Family history of the patient reveals the risk of developing peanut allergy. Skin test, blood test, and elimination diet are the other diagnostic tests.

• Skin prick test – a small amount of allergen is placed on the palm. The skin at the test site is then pricked with a probe, allowing the allergen to get inside. A reaction in the form of an inflammation is a positive test for peanut allergy. 
• Blood test – increased levels of antibodies in the blood reveal chances of allergy to peanuts. The antibodies are specific for the allergen tested. 
• Elimination diet – in this method, the suspected food is eliminated from the diet for few days. Absence of symptoms with elimination is a positive response for peanut allergy. The food items may be reintroduced after a few weeks to see whether any symptoms are elicited. 

These tests help to differentiate between food allergy and food intolerance, which develops due to lack of enzymes that digest the particular food. 

Peanut allergy can be managed by avoiding peanuts and treating the symptoms of accidental exposure as soon as possible. Oral immunotherapy is a desensitization method in which a child with peanut allergy is given increasing doses of peanut-containing food over a period of time. 

Theory states that body gradually gets used to the doses of allergen and stops responding to the presence. If there is a serious allergic symptom, epinephrine injections are given. Auto injectors of epinephrine are now available and can be carried along to avoid an emergency.

Avoiding exposure to peanuts is the best way to prevent peanut allergy. As peanuts are very common ingredients of food, it is difficult to completely avoid the same. 

Those who have severe allergic reactions should carry the epinephrine auto injector. Always be vigilant and read the labels before having food.

Apis mellifica is suggested in homeopathy to alleviate the skin symptoms of peanut allergy. Natrum carbonicum helps to relieve digestive problems due to peanut allergy. 

Carbo vegetabilis is used to prevent weakness, bloating and flatulence associated with allergy. Herbal formulas are also used to relieve the symptoms, but most of them lack scientific evidence.

Lifestyle modifications are necessary in order to cope with peanut allergy.

Always read food labels and try to avoid foods if ingredients are not clear. Risk of cross-contact is more in self-serve buffets where same spoon may be used for different foods with and without peanuts.

Keep a vigilant eye and avoid them. Ensure that family, friends, and school authorities know about the allergy. Keep auto injector always, if there is a history of serious reaction.

Anaphylactic reaction is the major complication associated with peanut allergy. Exposure to nuts may induce life-threatening symptoms.