Kava Allergy
Hives, edema (swelling), and skin reddening.
Drinkers have enjoyed kava for millennia with minimal reports of adverse effects. The adverse effects of kava have traditionally been limited to nausea, lethargy, and dry skin. Over the years, we have noticed a trend developing in a very small fraction of new kava users. These new users will take kava for a few weeks or a month and then suddenly develop hives and/or flushing on their face and upper body. These users may even change the kava sources to find the same issue. This appears to occur regardless of whether crude extracts (full spectrum) or powdered kava were consumed in the scenario.
Mast Cells: A mast cell is a resident cell of connective tissue that contains many granules rich in histamine and heparin [1].
Currently, it is thought that kava interacts with mast cells in several ways.
Elevation of free calcium levels is a critical step in mast cell activation. This was investigated with regard to kava. Kava was observed to robustly elevate free calcium levels in a dose-dependent manner [2].
Traditionally prepared kava can cause degranulation of mast cells, which releases histamine and other molecules from the vesicles of the mast cells, which can cause allergy-like symptoms [2].
Mast cell activation and degranulation is histamine release, which can be observed in these instances as hives or full flushing. Other symptoms of mast cell activation include abdominal pain, diarrhea, and a runny itchy nose. Mast cells are concentrated in areas of the skin near follicles, sebaceous glands, and sweat glands [3]. We already know from long-time kava drinkers that these sebaceous glands and follicles are slightly affected, as evidenced by dermopathy and sties. People experiencing hives and flushing are likely to have other allergic issues related to mast cell activation. Allergic reactions occur when the allergy antibody IgE binds to allergens to activate mast cells and release histamine. Antibody IgE levels were significantly elevated among kava users [4].
In conclusion, if you have started drinking kava recently and are experiencing hives and skin reddening, it is best to immediately quit kava. Some people have attempted taking antihistamines; however, it does not change the physiology of why excess histamine is being released in the first place. It is best if you find yourself in this situation to stop.
[1] Mast cell. (2021, February 27). Retrieved March 17, 2021, from https://en.wikipedia.org/wiki/Mast_cell
[2] Shimoda LM, Park C, Stokes AJ, Gomes HH, Turner H. Pacific island 'Awa (Kava) extracts, but not isolated kavalactones, promote proinflammatory responses in model mast cells. Phytother Res. 2012 Dec;26(12):1934-41. doi: 10.1002/ptr.4652. Epub 2012 Apr 4. PMID: 22473598; PMCID: PMC3773481. https://pubmed.ncbi.nlm.nih.gov/22473598/
[3] Fong, M., & Crane, J. S. (2021). Histology, mast cells. In StatPearls. StatPearls Publishing. http://www.ncbi.nlm.nih.gov/books/NBK499904/
[4] Clough, A. R., Jacups, S. P., Wang, Z., Burns, C. B., Bailie, R. S., Cairney, S. J., . . . Currie, B. J. (2003). Health effects of KAVA use in an eastern Arnhem Land Aboriginal community. Internal Medicine Journal, 33(8), 336-340. doi:10.1046/j.1444-0903.2003.00405.x