Route Of Exposure

Anise is an annual herb cultivated in many countries but native to Southern Europe and the Mediterranean. A member of the Apiaceae family, it is related to Caraway, Dill, Cumin, and Fennel. The dried fruits have been used for centuries for flavouring drinks, pastries, and candies. The ancients prized it as a medicinal plant.

Anise grows up to 60 cm high, is umbrella-shaped and has lacy leaves and delicate white flowers resembling Parsley. The fruits, often incorrectly termed “seeds”, are covered with short hairs, and each contains two gray-brown, oblong, approximately ½ cm seeds with light ribs.

Anise fruit contains about 1.5-4% volatile oil (quite a low proportion for a spice), which is about 80% antheole. Anise also contains coumarins.

One of aniseed’s main uses are for Anise-flavoured alcoholic drinks: Raki from Turkey, Ouzo from Greece and Pernod and Anisette from France. In Western cuisine, Anise is found mainly to candies (most commonly licorice), breads, cookies and cakes. In Middle Eastern and Indian cooking, the variety of Anise-flavoured foods is wider: soups and stews often feature Anise. The young leaves may be eaten raw or cooked, and can be a flavouring or a garnish.

The essential of the seed may flavour pickles, Aniseed balls, ice cream, chewing gum, and other foods. Oil of Star Anise may substitute for oil of Anise.

The oil is also used in perfumes, soaps, mouthwashes, toothpastes and other toiletries. Anise and its oil have been used to relieve flatulence and as a cough suppressant, sedative, and expectorant.

The plant is an ingredient of potpourri.

Clinical Relevance

Allergen description

No allergens from this plant have yet been fully characterised.

The main IgE-binding proteins in Aniseed extracts have been isolated and reported to be approximately 48, 42, 39, 37, 34, 33, and 20 kDa in size.

Potential Cross Reactivity

An extensive cross-reactivity among the different individual species of the Apiaceae family could be expected and has been reported to occur, in particularly in the case of the many positive serum- and skin-specific IgE results obtained with Carrot, Parsely, Anise, Fennel and Caraway in patients allergic to Celery. In vitro studies have concurred: enzyme immunoassay inhibition studies in a patient showed cross-reactivity among the IgE components from Aniseed, Caraway, Coriander, Fennel, and Dill extracts. A study reported that a major IgE-binding component from Coriander was observed to have a closely related pattern of IgE binding to Coriander, Dill and Anise extract, the results suggesting that the botanically related spices Coriander, Anise and Dill contain common IgE-binding structures.

Clinical observation has also shown that patients with Mugwort and Birch pollen allergy frequently have hypersensitivity to spices of the Apiaceae family. The term “Celery-Carrot-Mugwort-condiment syndrome” was proposed. The Bet v 1- and profilin-related allergens were reported to be responsible for Type I allergy to Anise, Fennel, Coriander and Cumin, all members of this family.

Clinical Experience

IgE-mediated reactions

Anise may commonly induce symptoms of food allergy in sensitised individuals, in particular in individuals who are allergic to Mugwort and Birch pollen or in Celery-sensitive patients. In a study of Celery- and pollen-allergic individuals, 50% of patients were reported to have specific IgE to anise. Allergens in spices are particularly risky due to their hidden presence in many dishes.

Reactions to Anise may be severe. In a series of patients with "idiopathic" anaphylaxis on history, 7% were not truly idiopathic, and an offending allergen could be identified and anaphylaxis provoked with the food on challenge. Foods included Aniseed, Cashew nut, Celery, flaxseed, Hops, Mustard, Mushroom, Shrimp, Sunflower, and Walnut.

Urticaria as a result of contact with Anise has been documented.

Occupational exposure to Anise may occur in spice factory workers and in liqueur and spirit manufacturers. Occupational allergy to Aniseed in a patient, with rhinoconjunctivitis and gastrointestinal symptoms has been documented. Skin-specific IgE and Aniseed oral food challenge were positive.

Occupational asthma was reported in a butcher. A significant fall in PEFR was observed when the patient handled Aniseed, and this supported the diagnosis. Skin-specific IgE tests carried out with 13 spices showed positive reactions only to Aniseed extract. The patient had high levels of specific IgE antibodies to Aniseed. A bronchial challenge test with an Aniseed extract showed an immediate response without a late response. The study's findings suggested that the respiratory symptoms in this patient were induced by the inhalation of Aniseed dust through an IgE-mediated immunologic mechanism.

Occupational asthma and rhinitis to licorice (dust), Mace, Aniseed, Coriander and Iris root in an Anise liqueur factory worker were reported

Other reactions

Chronic, ultimately fatal poisoning with alcohol-free Anise aperitif has been reported. An increased amount of ingested glycyrrhizinic acid may result in chronic hypokalemic myopathy and rhabdomyolysis with acute renal failure.

Present in a herbal product, Anise may increase the risk of bleeding or potentiate the effects of warfarin therapy.