Histamine Hydrochloride

Histamine exists naturally in our body. It is produced and stored in gastric cells, neurons, in the granules of mast cells and basophils, and in other cells. It is a neuronal neurotransmitter (Kovacova 2015) and an immunostimulant that protects lymphocytes. ^{(EMA 2013)}
It is used as a single dose in certain diagnostic tests and associated with interleukin II in the maintenance treatment of acute myeloid leukemia in two daily doses subcutaneously in ten cycles of 21 days with breaks of 3 to 6 weeks.

As of the last update, we found no published data on the excretion of histamine in breast milk.

Its pharmacokinetic data (wide volume of distribution, short half-life and alkaline pKa) make it very unlikely that significant quantities will pass into breast milk.
Histamine is rapidly cleared from plasma, with a half-life elimination of between 3 and 11 minutes according to Hale 2017 p450 and Middleton 2002, and 0.75 to 1.5 hours according to EMA 2013, clearance being twice as rapid in women. ^{(EMA 2013)}

Breast milk also has the power to degrade histamine because it contains the enzyme histaminase as an anti-inflammatory factor ^{(Lawrence 2016 p183)}. In other words, the little that may have passed into the milk is destroyed in the milk itself and will not reach the infant.

This same enzyme, histaminase or diamine oxidase (DAO), present in the small intestine and ascending colon (and kidney), destroys ingested histamine and normally prevents significant amounts from entering plasma. ^{(Kovacova 2015, Kanny 1999)}
Thus, its low oral bioavailability makes it difficult for the infant to enter plasma from ingested breast milk, except in premature infants and the immediate neonatal period in which there may be greater intestinal permeability.

Some expert authors consider it prudent to wait two hours after exposure to breastfeed. ^{(Hale 2017 p450)}

See below the information of this related group:

• ATC R06A: Antihistamines for systemic use.