Hi. That's one drawn strait out of the pages of my life. Antihistamines such as Zyrtec or Claritin aren't an issue for me, but Sudafed is: on account of which I'm just now emerging from a miserable cold without benefit of the little red pills, even though I could take Claritin for various minor allergies without apparent effect. BUT, when I go to the Wikipedia article on Vasoconstriction, a different picture emerges altogether:

Factors and individual mechanisms

Factors that trigger vasoconstriction can be of exogenous or endogenous origin. Ambient temperature is an example of the former. Cutaneous vasoconstriction will occur because of the body's exposure to the severe cold. Examples of endogenous factors include the autonomic nervous system, circulating hormones and intrinsic mechanisms inherent to the vasculature itself (also referred to as the myogenic response).

Exogenous medications

Examples include amphetamines, antihistamines and cocaine. Many are used in medicine to treat hypotension and as topical decongestants. Vasoconstrictors are also used clinically to increase blood pressure or to reduce local blood flow. Vasoconstrictors mixed with local anesthetics are used to increase the duration of local anesthesia by constricting the blood vessels, thereby safely concentrating the anesthetic agent for an extended duration, as well as reducing hemorrhage.[2]

The routes of administration varies. They may be both systemic and topical. For example, pseudoephedrine is available systemic (i.e. orally ingested tablets like Sudafed), and topical (such as nose sprays like phenylephrine Neo-synephrine, and eye drops for pupil dilation purposes).

If I had to guess, I would say that it must be an issue of degree, where Sudafed is guaranteed to put me into a flair, while those few antihistamines I've been exposed to since getting RSD 11 years ago have gone through me like water. Either that, or antihistamines are somehow more selective in their vasoconstriction where as Sudafed hits with a clearly systemic effect. Dunno. Still, a quick PubMed search of "Histamine antagonist vasoconstriction" produced 500 hits "on the nose," many clearly addressing the vasodilative effects of histamines, so there must be some there, there.

Wish I could be more helpful.

Mike

I believe the bottom line about antihistamines is that they block the vasodilation of histamine in allergic reactions.

This means their effects are not global on all smooth muscle in the vasculature.

Sudafed being a pressor amine, will cause contraction in smooth muscle and hence affect many blood vessels. Sudafed raises blood pressure. Sudafed has no effect on histamine receptors. The pressor actions of norepi effects (increase) in mixed antidepressants also raises blood pressure in many patients. (Effexor, Cymbalta, Savella)

Antihistamines (first gen) however do not raise blood pressure at normal doses. And the first generation type, have anticholingeric effects, and may lower blood pressure in some patients. The vasoconstriction that antihistamines cause is more or less focused on the tiny capillaries that are dilated by histamine reactions.

Mike, thank you for your response to my post. I will try to answer your question, but, as you know, we are all different people sharing the same disorder. Or, is it the same disorder? I read somewhere that 'they' aren't even sure it is all the same disorder.

I do not fear injuring myself as far as ice burns or lesions. I don't believe I would ever go that far. After all, my skin is so sensitive I can hardly touch it myself. I expect the pain would be warning enough. I was referring more to the root molecular (?) level in the muscles and such. Please forgive me. I am not nearly as learned as you regarding medical terms and processes. I'm not sure about sympathetic mediation, vasoconstriction, alleles or innervation. I do know what a capillary is, and believe me I too complain about the onset of winter ... as well as the duration.

I am surprised that my response is so unusual. There are others on this forum that have the burning and swelling as I do. They avoid the heat too. Am I the only one who uses ice to relieve the swelling and burning when it is at its peek? Like I said, I wish I had landed here sooner.

I was diagnosed with CRPS in February 2010; Type 2 Stage 3. I hadn't heard of the syndrome until my diagnosis. I was stunned. My husband and I hurried home from the Doctor's office and poured over the net to get some idea of what lay ahead for us. Looking back, and now knowing the symptoms of CRPS, I realize that I have had some of the symptoms prior to 2008. My injury to L5-S1 and subsequent surgeries to my back and left foot and ankle were in November 2004.

My symptoms include the burning pain, swelling, bright red to purple to black changes in color, extreme sensitivity to touch on the affected areas, extreme cold and hot temperatures of the legs and feet, blotchiness (skin often appears to have a giraffe print), thin and dry and sometimes peeling skin, changes in nail texture with pits ridges and spooning, muscles are so stiff and spastic with jumping and twisting as if they have a mind of their own (I have also been diagnosed with Dystonia) that I find it difficult to walk or rest depending on the day and how feel, muscle and bone atrophy, and the pain so intense that sometimes I just cry. The pain goes from burning to pins and needles to stabbing to shooting to deep muscle pain. Sometimes it feels like a hot poker is being rammed through my foot and up my leg all the way to my pelvis. Sometimes it itches, sometimes I feel like I have worms crawling under my skin. Believe it or not, you can see them (myoclonus)! That poker pain and worms etc. run from my feet up my legs to my hips to my pelvis and lower back and somehow it lands in my left eye causing a migraine. My bladder no longer functions due to the spasticity; I have to cath 3 times a day to empty. Sex? no; are you kidding? I had surgery in 2012 to correct the curling legs and toes. The Ortho severed the muscles in my toes and ankles, and reconfigured others. Yes; severed; both left and right. I was walking on the side of my twisted foot with the toes on both feet severely curled under. The Doctor used screws and braces and a scalpel. It was drastic but we all decided (Doctors, family and me) that I had no other options if I wanted to walk at all. I am disabled to the point that I cannot walk but from the bedroom to the kitchen to the toilet and back. I use my electric wheelchair when I leave the house.

I'm sure you know that this list is by no means a definitive list. It is as well as I can remember it for now.

As far as the sympathetic nerve blocks, I have had 2 but only after my diagnosis. They worked for about a day, maybe a day and a half. As you know, there is no definitive test for a diagnosis. I have had MRIs, bone scans, emgs, thermography, sweat testing, etc. All led to my diagnosis.

I know this is I dreadfully gloomy. I appreciate your interest in my story though. Please tell me what is it that you are looking for? ... In laymen's terms (?).

sallysue, et. al.,
Your inquiry leads me to question Benadryl. I have occasionally used this antihistamine to clear my head of congestion. I note too that in the Emergency Room on one occasion, the Doctor there administered it to me (in adition to Adavan) via IV to relax me after a seizure (a reaction to Tramadol). Any thoughts as to its benefit or adverse affect on us CRPSers from the use of Benadryl?

Hi djhasty, thank you for sharing your story and what brought you here. I'm sure you are sooo happy you found this forum like I am. Wow, you have been thru so much. Welcome- am sure you will find the experiences of others, their shared knowledge, coping skills, their support of yourself, will lift you up and comfort you. Looking forward to your posts. loretta

Looks like mrsD nailed it: Post 42, above. If the vasoconstrictive effects of antihistamines are confined to histamine in allergic reactions, then there's nothing to worry about, unlike Sudafed which is an equal opportunity vasoconstrictor throughout the body, or in other words, operates "systemically." Bottom line: I am not aware of any reason to be concerned about Benadryl's interaction with RSD/CRPS.

Mike

I would also investigate that skin mottling you describe as "giraffe skin". This sounds alot like livido reticularis... and this
symptom is connected to autoimmune diseases.

Given that some new reports of treating CRPS with IVIG treatments, added to a potential of having an autoimmune thing going on, might lead to a new treatment for you, Djhasty.
Have you been tested for ANA and other autoimmune markers?

While RSD is a form of neuropathy, the intolerance to cold differs from patients with Peripheral Neuropathy. Many of us at PN here use cold treatments to minimize our pain. Heat for us, makes things worse as a rule. This is the reverse of the most common posts here about heat helping with RSD pain.

Something to think about.

I did see that Wiki article also, fmichael. It is very confusing when writers lump in antihistamines with drugs like amphetamine and cocaine. That is very misleading!

And also, many of us at PN, find Benadryl very helpful for PN pain. Benadryl is also used for movement disorders and dystonia. That effect may wear off with time however.

Djhasty -

Once again, point to mrsD! I would strongly urge you to be worked up by a rheumatologist. You may well have developed an autoimmune condition on top of your CRPS. And as mrsD suggests, there are autoimmune treatment that can be highly beneficial to someone with CRPS, even though it may take a classic autoimmune Dx for your insurance company to approve them: we call those silver linings.

Good luck and let us know.

Mike

PS I too had an immune system that went crazy in the first three years after the onset of my CRPS symptoms, including, but not limited to pulmonary sarcoidosis and, with minimal risk factors and a clean nuclear medicine scan a few months earlier, what turned out to be a relatively minor heart attack out of nowhere. (For anyone who's counting, it was a 100% occlusion of the mid-LAD, diagnosed over a year later: let's hear it for "good collateral blood flow"!)

Thank you mrsD and Mike.
I did have a full work up for markers connected to autoimmune disorders. MCTD does run in my family (my older sister). I was even sent to an Oncologist who ran the tests again and performed a bone biopsy because of wide spread bone marrow abatement. I had 2 biopsies in fact. Nothing showed up other than a terrible scare on my part. As it turns out the Docs now expect that the bone issue is connected to the CRPS.

I do have high blood pressure and a bit of liver dysfunction that developed after I started taking the antiinflamitories prescribed for CRPS. The Docs are keeping an eye on it. My Internist tells me that I am pretty healthy other than the CRPS.

Thank you both for your input. I'll bring it up again with my Doc when I see her in May.

PS. Gees. Now I'm wondering about the ice thing again. Could it be causing the giraffe mottling? I'm going to ask the Doc her opinion about the ice thing too. For now, I'll try to set it aside, but as was noted above I am desperate. The heat that radiates off my burning red feet and legs sure make me long for a quick fix. Believe it or not, ice does help some for the immediate burn. As far as what damage might be happening in the long run ... I don't know yet.

Thanks again.

Yes! After looking at pics on the net, that is my giraffe skin!