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    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of and finding treatments for complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia (FM), long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

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Do Antihistamines improve your OI?

Does your Orthostatic intolerance improve with antihistimines?

  • I haven't taken them

    Votes: 3 18.8%
  • no

    Votes: 6 37.5%
  • they make me worse

    Votes: 0 0.0%
  • a bit

    Votes: 6 37.5%
  • alot

    Votes: 1 6.3%

  • Total voters
    16
Messages
45
Location
UK
I've read a lot about there being a third type of pots which is due to mast cell activation. It is possible that this type of pots would be helped by antihistamines. Benadryl (diphenhydramine) helps my Pots significantly. I've added a couple of links to papers in my next post.
 

Sushi

Moderation Resource Albuquerque
Messages
19,935
Location
Albuquerque
If you have an antihistamine that has sudafed in it, it should help OI as a vasoconstritor. It was one of the earliest meds prescribed.

Sushi
 

ukxmrv

Senior Member
Messages
4,413
Location
London
Sudafed does help me with OI but other antihistamines (like Benaryl make me sleepy only or have no effect).
 
Messages
45
Location
UK
This is one of the papers which talks about antihistamines helping.

The explanation of the finding is postulated to be the release of a vasodilator from activated mast cells, supported by a raised urinary methylhistamine.4 These patients, as might be expected, may be worsened by beta-blockers but may respond to H1 and H2 histamine blockers with or without alpha-methyldopa. This third sub-type of POTS may present raised blood pressure at times in association with flushing and offer a differential diagnosis from phaeochromocytoma. This sub-type may only be a small percentage of those with POTS but, for them, there may be a specific therapy, anti-histamines not beta-blockade.

http://europace.oxfordjournals.org/content/13/3/306.full#ref-4
http://hyper.ahajournals.org/conten...3e679af5223908c9a4acdbe4&keytype2=tf_ipsecsha
 

charlie1

Senior Member
Messages
315
Location
Canada
@ Aquila, thanks for posting the articles.
I find improvement in my dysautonomia symptoms (POTS and vasovagal sycompe) when taking sudafed.(decongestant)
Lately I've added H1 and H2 (75 mg zantac am & pm and am Reactin) to my daily SR180 mg of Mestinon and .1mg florinef. I've done this to see if it might point to signs of me having MCA.
The h1 and h2 addition has stopped my flushing episodes but unsure if I can attribute any OI benefits from it.
 

Shell

Senior Member
Messages
477
Location
England
Funny you should ask that. it's something I've been wondering about. I was thinking about experimenting on myself with Piriton to see if it would help the OI - which, bizarrely is much worse now I'm on Ivabradine. I came off the drugs for three days and saw no improvement so I thought I'd better get back on them.
Still waiting and hoping for Hyper POTS tests ...
 

xchocoholic

Senior Member
Messages
2,947
Location
Florida
My story ... When I started taking Zyrtec it helped my OI but then it stopped helping. I seem to do this with a lot of things tho. I suspect that I'm possessed by an evil spirit. :alien::lol: :)

Benadryl knocks me out as does Vistaril and that's not good for orthostasis. And Sudafed dried me out too much.
 

Sherlock

Boswellia for lungs and MC stabllizing
Messages
1,287
Location
k8518704 USA
I don't have OI much. But diphenhydramine lessens polyuria (usually) for me, so that presumably should increase blood volume.
 

IreneF

Senior Member
Messages
1,552
Location
San Francisco
Sudafed has always dried me out too much. Last time I took it, it made me so dizzy I had to go down the stairs one step at a time while clutching the rail.

I take the antihistamine loratidine, aka Claritin, and it doesn't do a thing for OI or POTS. Benadryl knocks me out.
 

Shell

Senior Member
Messages
477
Location
England
This is an interesting question as I've been learning more about norepinephrine and dopamine. Being a slow and foggy person I hadn't twigged (embarrassingly) that norepinephrine is noradreneline. Once, what's left of my brain cells grasped that I did start to wonder if I should try antihists.
What I can't help wondering though is, if histamine is being effected by low NorEp then why aren't more of us very allergic to stuff. I have a severe allergy to mango's and a mild allergy to oranges and orange juice (well, not that mild, it effects my breathing, but nothing else) and a mild dose of hayfever. If my OI was histo lack wouldn't I have more allergies?
OTOH my OI is so bad at the moment it's worth a try.
 

xchocoholic

Senior Member
Messages
2,947
Location
Florida
Shell

In my case it was because I didn't recognize that allergies present in a wide variety of ways.
I was completely familiar with the runny nose and watery eyes reaction but not the others. If you look up allergic and non allergic reactions you'll find a long list. Vasodialation is one. Tc .. X
 

ukxmrv

Senior Member
Messages
4,413
Location
London
My allergies started with the acute onset viral ME. I do have a very allergic family though and many extended family members are as bad as I am. We also have ME in the extended family (and that includes inlaws)
 

heapsreal

iherb 10% discount code OPA989,
Messages
10,086
Location
australia (brisbane)
There was something written last year or the year before from dr bell saying how he has found codeine helpful for pots/oi. Generally opiates vasodilate and then things like sudafed vasoconstrict, it seems confusing as to what will help. I suppose we dont know unless we try?? Sudafed (psuedoephedrine)itself isnt an antihistamine but an adrenergic stimulant in the same class as adrenaline etc.