Tryptase Testing

[enko]

I'm about to have one, but since I'm on H1-blocker, should I make a break before the test? How long should it be?

[juliegee]

I'm about to have one, but since I'm on H1-blocker, should I make a break before the test? How long should it be?

To be honest, I don't think anyone REALLY knows. I've certainly never seen studies addressing this- although the question is posed often. The current medical stance (based more on practice & current understanding rather than actual medical studies) is that taking an antihistamine will NOT affect serum tryptase testing because antihistamines simply blocks histamine; and shouldn't affect level of the serum tryptase protein.

What does your doc say? How do you do without your H-1?

Julie

[enko]

Thank you Mack's Mom for answering!

To be honest, I didn't ask my GP. It didn't occur to me to ask. I will next time I'll see him (probably tomorrow or in the day after it). Although I'm not sure he'll know the answer.

Actually I'm on my H-1 all the time for last 3.5 mo. But I did make the same mistake twice Once I went for a 4 days long trip and forgotten to take the pills. At the end of the day I've arrived I had itching (that's "normal" for me because it seems that the med wears off in the afternoon, at least for me). Next day I had itching and was feeling more tired. Day after I was very itchy and had a headache. On the next day I couldn't stop scratching, it was unbearable! Scratched spots became all red again (at least the med helps with the dermographism). When I've got home and took the med, I couldn't be more grateful for it.

Next time I've done that stupid mistake was just recently. I've forgotten about the med because I was in a hurry in the morning before going out. When I've realized, it was too late. I was extremely tired, confused, itchy and had a headache. Plus the day was hot and it makes things even more worse for me. Swollen neck is a standard with or without the med And you want to know the best part? I was recently on a checkup at my dermo, who said: "Oh, wow, your dermographism is negative, that's great, you are getting off the med in a months time". What???

But in the end.. if I need to get off it for the test, I guess I'll have to go through it..

[juliegee]

I don't think you have to get off of it; at least according to what the medical establishment currently recommends- I just think that no one really knows the effect that antihistamines have on serum tryptase testing. To my knowledge, it hasn't been studied.

If it makes you feel better, i have similar effects when I try to get off of my meds. I feel OK the first day, then the symptoms set in For me, the autonomic stuff is awful- fast HR, low BP, tight throat, tight chest, hives, severe GERD, headache, etc. If I tried to do that for multiple days, I am certain I would have an anaphylactoid reaction. And, yes- H-1's prevent dermatagraphism. But, usually when you stop them, it comes back.

Use your judgement, but be safe re. the H-1. If you feel safe, but uncomfortable...you might get a more accurate result if you skip a dose or two. Do what feels right & SAFE for you

Julie

[enko]

If I would stay on H-1 and go for testing and my results would be "normal" or "low", I would probably eat myself up with thinking that maybe the med had something to do with it. Soooo I'll probably take a pause and go for the test. If I'll see that I won't be able to make it, I'll start it again. I'll try to call the lab tomorrow, maybe they'll have more info.

I'm guessing that Zoloft won't have any effect?

[Godsgal]

My good friend just saw Dr. Castells (mast cell expert) and she tested my friend up & down for multiple different types of tryptase testing and she never told her to get off her antihistamines. And just a thought....both of our tryptase levels are normal and we still have mast cell disease. It mostly rules out systemic mastocytosis. Correct me Julie if I'm wrong

[juliegee]

My good friend just saw Dr. Castells (mast cell expert) and she tested my friend up & down for multiple different types of tryptase testing and she never told her to get off her antihistamines. And just a thought....both of our tryptase levels are normal and we still have mast cell disease. It mostly rules out systemic mastocytosis. Correct me Julie if I'm wrong

You're absolutely right, but YOU and your friend are major exceptions to the rule as you both have systemic mastocytosis, with low serum tryptase. Really makes me wonder how many thousands of us are missed???

Dr. Castells did my testing too & I did NOT come off of my meds. I was just pointing out that no one has really studied how antihistamines affect serum tryptase testing. I have had mine re-tested every 6 months by my local allergist (from Mayo) and I have never stopped my meds. It would be interesting to have the test if I could get off meds....so I see where you are coming from Enko. Just be safe. High serum tryptase just rules out systemic mastocytosis (unless you are Jared & friend ) A normal result does not rule out mast cell activation disorder.

[enko]

I'll know more tomorrow, but to be on the "safe" side, I'll probably skip few doses.. I'm not really smart what to do..

[Lethargic Smiles]

I have this same question about tryptase. I'm a total newb to MCAD. This study from 2006 (based on what I read in abstract) found serum tryptase level were lowered by second generation antihistamine usage: http://www.ncbi.nlm.nih.gov/pubmed/16843643 If I get tested, I'm thinking I will quit taking my NyQuil each night and also quit Singular (not an antihistamine, but sometimes used for MCAD).

[Chaos]

I believe most of the studies are showing that people with MCAD don't have elevated tryptase levels. Usually that is just found in people with systemic mastocytosis.

If you read thru this paper that Alex posted https://www.novapublishers.com/catalog/product_info.php?products_id=42603 by Dr. Afrin it discusses (in the first several pages) what they are finding about tryptase levels in MCAD patients.

The NyQuil, being over the counter, you could probably quit on your own, but you might want to check with your doc before stopping the Singular. You might want to check the half life of those meds too if you do decide to stop so you know how long you need to be off them before you do the tests.

I know when I haven't stopped meds before tests (docs have said to continue them) then I'm always wondering how much that affected my results.