Garlic is a food which may result in allergy symptoms in sensitised individuals.

Garlic Allergy Test: Allergen Exposure

Garlic has been known to humans for millennia, and used as both a flavouring and medicine for at least the past four centuries. In some cultures the use of garlic has additional religious significance. Today, garlic is produced and consumed on a global scale, with the major suppliers of the crop being the United States (mainly California, Texas and Louisiana), France, Spain, Italy and Mexico. Fresh garlic is available at all times of year.

Garlic’s edible bulb or “head” grows beneath the ground. This bulb is made up of sections called cloves, each encased in its own parchment-like membrane. Garlic has a strong, pungent and characteristic aroma and flavour.

Garlic bulbs are eaten, either raw or cooked, as flavouring.. They are usually peeled before use in recipes. Crushing, chopping, pressing or pureeing Garlic releases more of its essential oils and provides a sharper, more assertive flavour than slicing or leaving it whole. Garlic is readily available in forms other than fresh, such as dehydrated flakes or powder.

Garlic salt is Garlic powder blended with salt and a moisture-absorbing agent. Garlic extract and Garlic juice are derived from pressed Garlic cloves. One side-effect of Garlic is that it remains with the body long after it has been consumed, affecting breath and even skin odour.

The stems, leaves, flowers and seed can be eaten raw or cooked, and are milder than the bulbs.

Garlic can reduce nasal congestion and lower blood pressure and blood cholesterol (studies suggest that garlic is responsible for the low incidence of arteriosclerosis in areas of Italy and Spain where consumption of the bulb is heavy).

It has been employed as an antiviral, antibacterial, fungicidal, vermifuge, vasodilator, expectorant, diuretic, antiasthmatic, antispasmodic, febrifuge, stomachic, skin-soothing, tonic, and immunostimulant agent.

Cloves of garlic are sometimes spread among stored fruit to delay rotting. The juice is also used as glue for mending glass and china.

Garlic Allergy Test: Allergen Description

No allergens present in garlic have yet been characterised, however various protein bands have been detected.

Garlic Allergy Test: Potential Cross-Reactivity

An extensive cross-reactivity among the different individual species of the genus could be expected, as well as to a certain degree among members of the family Alliaceae (previously categorised as Liliaceae), such as onion, leek, garlic, asparagus and chives.

Garlic Allergy Test: Clinical Experience

Garlic can induce symptoms of food allergy in sensitised individuals. Garlic is a well-known cause of contact dermatitis and asthma. However, it is thought to be an uncommon cause of food or other allergy in children.

In an Indian study of 24 children aged 3 to 15 who had documented deterioration in control of their perennial asthma, IgE antibodies to Garlic were documented in 14.

Garlic may result in anaphylactic reactions, as described in a 23-year-old woman who had eaten young garlic.

Occupational asthma and rhinitis have been reported, which may have an onset long after work with the substance. Occupational allergy to Garlic dust has also been reported.

Other reactions

The spectrum of garlic-related skin adverse reactions comprises irritant contact dermatitis (with the rare variant of zosteriform dermatitis), pemphigus, contact urticaria, protein contact dermatitis, and allergic contact dermatitis, as well as combinations of these.

Patients have experienced second-degree burns of the forehead, breast, and other parts of the body, induced by topical application of crushed garlic.