Works wonderfully for both my seasonal allergies and my my histamine over load.
I am so grateful that my current Doctor suggested me to try these supplement (D-Hist and Sinatrol). It works great and not side effects whatsoever. I will highly recommended to anyone with severe allergy symptoms.
I really like D-Hist. It works well and I don't get the side effects (constipation) that I do with other antihistamines. I mainly have bad spring allergies, when the trees are budding and this takes care of it as well as Claritin. It's so much more expensive, but I think it's safer in the long run.
I've used D-Hist for over 10 years for moderate allergies. 'For me' it works far better than Claratin or Allegra. Especially in opening up my ears which none of the others do. I like I can adjust the dose depending on severity. Only downside is the price has increased 30% or more in that time, I suppose due to demand. It's worth a try if the OTC meds aren't cutting it for you.
I like this supplement, it seems to work. But my allergies have been so bad that I have had to use the maximum every day.