Does spirulina improve allergies?

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    Last Updated: May 16, 2025

    Spirulina has shown potential in reducing symptoms of allergic rhinitis, and some studies indicate that it may be as effective as cetirizine for nasal itching and sneezing and more effective for runny nose and nasal congestion. Its effects may be associated with its interaction with the immune system, specifically by lowering interleukin 4 levels and inhibiting histamine release.

    Spirulina has shown some promise for reducing symptoms of allergic rhinitis, but research is still at an early stage.

    A few studies have found that compared to a placebo, spirulina reduced symptoms of allergic rhinitis.[1][2] Interestingly, a randomized controlled trial found that spirulina supplementation given daily for two months was as effective as cetirizine — a commonly-used allergy medication — at reducing symptoms of nasal itching and sneezing and more effective than cetirizine at reducing rhinorrhea (runny nose) and nasal congestion.[3]

    This effect may be due to how spirulina interacts with the immune system. More specifically, spirulina may reduce levels of interleukin 4 and prevent the release of histamine from mast cells.[4][3][5][6]