|The Effects of Nigella Sativa on Allergic Rhinitis
Wadiah Backer, Emad Khoshak, Tarek S. Jamal, Kamal J. Daghistani
Saudi Journal of Oto-Rhino-Laryngology Head and Neck Surgery, Vol. 7. No. 1
Allergic rhinitis represents a global health problem. It is common disease with a worldwide distribution affection at least 10 – 25 % of the population and its prevalence in increasing. It affects approximately 10 -20 % of North Americans and between 10 and 15 % of North Europeans. Perennial rhinitis is probably more common in adults than in children. It can alter the social life of patients interfering with school performance and work productivity. The cost of lost productivity and medications can be more than $2 billion. Allergic rhinitis can be defined as a symptomatic disease of the nose, induced after allergen exposure. It is an IgE-mediated hypersensitivity disease of the mucus membranes of the nasal airways characterized by sneezing, nasal obstruction and rhinorrhea. It is closely associated with asthma suggesting the concept of "one airway, one disease". Allergic rhinitis is mostly found in association with exposure to areollergens (house dust, house dust mite, moulds, animal dander, yeast and pollens). It can be either seasonal or perennial. Perennial rhinitis with severe seasonal exacerbations is common.
Negella sativa (N.S.) has been reported to have a bronchodilator and spasmolytic action which could be useful in asthma patients. The volatile oil of N.S. is known to contain thymoquinone. This has a carbonyl fraction with extremely low toxicity. It shows a dose-dependent inhibition of histamine release from rat mast cells. The percent inhibition is significantly higher when the drug was kept in contact with the cells before antigen challenge than when the drug was added together with the antigen release. The in vivo protective effect of nigellone was more evident than in vitro effect. The aim of this study was to find out the effect of N.S. seeds on the symptomatology of allergic rhinitis comparing it with placebo and Loratadine.