Depression and anxiety can cause serious problems in an otherwise productive life. These conditions frequently run in families.
Very high blood levels of histamine can significantly increase a person’s risk for depression. Because its origins differ from other forms of depression, high histamine depression may not respond well to the usual depression treatments.
A neurotransmitter in itself, histamine stimulates the release of important mood neurotransmitters like serotonin, norepinephrine and dopamine in the brain’s hypothalamus. 
The condition of having abnormally high levels of histamine is called ‘histadelia’, or ‘undermethylation’. This condition creates an imbalanced amino acid cycle, resulting in low serotonin levels. Serotonin is a neurotransmitter that is believed to be responsible for maintaining mood balance. It is thought that a deficiency of serotonin leads to depression.
Many medical practitioners remain ignorant of the histamine-depression link. Michael Lesser, M.D., author of “The Brain Chemistry Plan,” states that few clinical psychiatrists focus on elevated histamine levels as a cause of depression.
Treatment for high-histamine depression
- Regularly take the supplements listed in ‘Is Food Making You Sick? The Strictly Low Histamine Diet’, especially vitamin C, which is a potent antihistamine.
- Follow a low histamine diet.
It can take 3-6 months to resolve this chemical imbalance. If treatment is discontinued, symptoms may return.
 Causes Of Depression – Histamine Imbalance. by Cindy L. www.holisticdepressionhelp.com