Another supplement to consider for the preventive treatment of migraine headaches is diamine oxidase (DAO). It is an enzyme that breaks down histamine.
Histamine is released during an allergic reaction and is present in many foods. It is one of the neurotransmitters that is involved in the process of migraine. A quarter of the population has insufficient amounts of DAO, which leads to inefficient metabolism of histamine. The largest amounts of DAO in the body are found in the intestines and the kidneys.
A group of Spanish neurologists published a study that showed that of 137 patients with migraines, 119 (87%) showed impaired activity of the enzyme.
The normal enzyme activity is a score of at least 80 histamine-degrading units [HDU]/mL. In a survey which was conducted in 2006 and again in 2012, migraine symptom scores correlated with enzyme activity. Symptom scores rose progressively as enzyme activity dropped below 80 HDU/mL, with scores almost twice as high in the 30-40 HDU/mL range compared with enzyme activity >80 HDU/mL.
Dr. Izquierdo and his colleagues in Barcelona conducted a double-blind, placebo-controlled trial of DAO oral supplementation, for the prevention of migraines in patients with DAO activity less than 80 HDU/mL.
Participants were men or women age 18 to 60 years old with an attack within the previous 6 months. Most of the patients were women, with only 8 men in each group.
The supplement contained 4.2 mg of DAO which participants took with a glass of water before breakfast, lunch, and dinner. The supplement was associated with a similar reduction in the mean number of attacks per month in the placebo and DAO groups, but the group that took DAO used significantly fewer triptan drugs (such as sumatriptan, Imitrex). These results are not overwhelming, but they possibly hide the fact that some of these patients had a very good response while others had none, which averaged out to a modest benefit. Considering that this a very benign supplement with no potential for serious side effects (unlike prescription drugs), it may be worth trying.
Histamine intolerance is defined by an imbalance of histamine and the histamine degrading enzyme diamine oxidase (DAO), which is mainly produced in the small intestine. Excessive amounts of histamine in the body can cause not only migraine and other types of headaches, but also diarrhea, nasal congestion, asthma, rashes, and other symptoms. People who are prone to severe allergic reactions with anaphylactic shock often have lower DAO activity. Diamine oxidase activity can be measured in blood, but the test is expensive and not very reliable. Instead of doing this test, try a low histamine diet or taking a DAO supplement. This is particularly worthwhile for people who in addition to migraines suffer from colitis (such as Crohn’s), allergic conditions, asthma, and celiac disease.
Here is an informative post on this topic on The Daily Headache blog.