Can histamine cause dermatitis

[Blondie1957]

For two years I have been having treatment for psoriasis but know I have been told it's dermatitis that is on my hands and feet can it be caused through histamines I really would love to get to know the cause is as this is so very painful when my fingers and feet split open and bleed it can sometimes get infected too and takes a long time to heal

[Dr Janice Joneja]

Several research studies have been conducted to find out if psoriasis and other types of dermatitis are associated with histamine excess. A report from Sweden in 1998 suggested that there is an increase in overactive mast cells in the skin in patches of psoriasis. Mast cells are white blood cells that reside in tissues and produce and store a number of inflammatory chemicals, including histamine. When mast cells are activated they release histamine and other biochemicals, which cause inflammation, and the symptoms of allergy. Compared to the skin of healthy volunteers, mast cells were higher in numbers, and the level of histamine in the skin and plasma was increased in the people with psoriasis. The authors found that ranitidine, an H2 antihistamine, reduced these effects to some extent. Later studies showed that some newer H1 antihistamines such as clemastine reduced the itch of psoriasis, but were sedating, therefore probably not acceptable for continued use. Unfortunately, at the present state of our knowledge, all that can be said about the connection between psoriasis and similar skin conditions is that there is some association with histamine, and that certain antihistamines may help to control the symptoms. Not a very helpful answer, I'm afraid. Perhaps a histamine-reduced diet might help to reduce the sources of histamine that we can control, and so decrease the total level of histamine in the body in the hope that it will have some positive effect on inflammatory conditions in the skin.