To recipes helpdesk

Question

Posted on: March 6 2013

Following the cessation of production of histamine provocation tests by the company HAL Allergy, we were forced to look for a personal preparation.

However, after a few questions about the colleagues, we got a lot of different formulas for this preparation. < br/> On the basis of a stock solution, different solvents with or without preservative (phenol) are used in different hospitals. Now our question is what the most suitable (stable) is, how to store (room temp. or refrigerator, light sensitive or not light sensitive) and what is the retention period (information received is from é é N from 1 week to 1 year).

Answer

For all your questions I would like to make the following fringe remarks:

  1. there is not only histamineHCl but also-phosphate, although the latter is not available in Belgium;
  2. both are sterilizable and by autoclaving and by filtration;
  3. both the pH and the added preservative can affect the operation of the solution;
  4. in terms of pH preferably +/-neutral;
  5. in terms of preservatives: phenol, parabens and also benzalkonium chloride (slightly less allergizing?). At pH = 7.4, phenol seems to me little meaningful as a preservative;
  6. Of course it seems most appropriate not to use a preservative but then one has to opt for a unidosis (2 ml). Multidose preparations must contain a preservative;
  7. autoclaving is preferred as a sterilization method;
  8. a solution of histamineHCl is chemically very stable. I believe that a retention period of six months may be accepted at room temperature. Some speak of 4 month, others of 12.