Cinetidine & Loratadine ect

[Rando21]

I’ve noticed I don’t seem to have night sweats or certain other issues (feverish ache sensation) with my CLL when I take Claritin(Loratadine). Is that just me? I did some basic research and found that several drugs in this class including Tagamet are being researched as beneficial for cancer. Anyone know of research Cimetidine (tagamet) and Loratadine (Claritin)? Is it ok to take antihistamines like loratadine, zyrtec, or allegra with CLL? Are any of the other names listed suspected as beneficial?

[Saju21]

hi newly diagnosed (3days) do cant give any cll experience. I have suffered chronic rhinitis for 20 years - hence CLL diagnosis was a shock as i expected that was the cause for elevated bloods. I take fexofenadine which is prescription only and anecdotally 10x otc antihistimines. Consultant says i can continue. Nothing to note between referral bloods and first consultancy tests over an 8 mth period.

[SofiaDeo in reply to Saju21]

Fexofenadine is no longer prescription only in the US.

[G1llHa1n in reply to SofiaDeo]

That's also now the case in the UK

[Saju21 in reply to G1llHa1n]

are you sure? Google search for online purchase and two sites say you need private prescription. I font yhink my gp would prescribe if they could make me pay. I should mayve have clarified that i am 2x 180mg tablet daily.

[G1llHa1n in reply to Saju21]

I've a packet here that I bought over the counter recently. I'm in the UK. I understand that this was quite a recent change here - previously it did need a prescription.

[SofiaDeo]

Since histamine and cytokines are interrelated in the body's inflammatory cascade, antihistamine combinations have been used and are being researched for various inflammatory conditions. It's great you found an agent that seems to help with your symptoms.

To my knowledge, none of any of the various antihistamines are absolutely contraindicated simply because we have CLL. Some patients may not react favorably to one or another, so it's more "patient specific" whether or not someone can, or should avoid, certain meds.

A quick glance shows me some researchers belive a combo of an H1 plus an H2 inhibitor work best; there is evidence the combo stabilizes mast cells better than a single agent alone.

I found a 2020 article indicating certain antihistamines appear to help BTK inhibitors work better. I say "appear" because this is in test tubes, not in the human body. I am sure someone is doing research in animal models, to see if this effect happens in living organisms, and potentially in humans.

sciencedirect.com/science/a...

[Pearlpink]

Hi. I started to take loratadine again when I was diagnosed with CLL and I found I felt so much better on it and less tired. I had very bad fatigue with my CLL and it really helped.

I’m on O&V (just started ramp up if venetoclax), and my consultant is happy for me to take the loratadine.

I used to get very bad hay fever and so was used to taking loratadine, but thought it was starting to make me tired. I now know that the tiredness was due to my CLL, and it now has the opposite effect.

There’s a recent observational paper suggesting loratadine and other histamines might be responsible for a reduction in certain types of cancer. Here’s the link:

ncbi.nlm.nih.gov/pmc/articl...

As it does me so much good and biologically makes sense I take it every day.

[Rando21 in reply to Pearlpink]

It seems to help my fatigue as well. As well as aches and like a localized feverish feeling I seem to get when I eat certain foods. Good to know I’m not alone on this one. Thanks for the article.

Have you heard anything about Tagamet? I read it may increase NK counts. Which seems interesting with the Loratadine. Either way, I need something for heart burn so, if there’s no risk? Why not

[LeoPa in reply to Rando21]

Which foods make you feel like that? Can you not eat them?

[Rando21 in reply to LeoPa]

Seems like mushrooms and smoked meats? Also, I am starting to suspect very sweet and/or greasy foods. I don’t really know why. It’s a very distinct though.

I’m recently diagnosed and just noticing certain potential patterns. Sometimes I’m not even sure what the cause might be but Claritin and an ibuprofen typically help or clear it up entirely.

[LeoPa in reply to Rando21]

I'd suggest to do an elimination test. Smoked meats area no-no anyways so I'd skip those. If you suspect greasy foods, have some pork belly in isolation. Not much. Then a few hours later observe how you feel as a reaction. Same with all other suspect items. Don't mix anything to not confound results. This way I found out that grains and all baked items with yeast give me gas and heartburn. Store bought milk gives me diarrhea. The list goes on. See this book for more info. I read it, executed it and found it helpful.

amazon.com/Your-Personal-Pa...

[Rando21 in reply to LeoPa]

Yeah I’d found a few things like that as well. For example, oat meal will give me horrible heart burn for some reason.

I may try the pork belly. When this happens it’s really obvious and seems to happen only after certain meals. It’s like clock work fatigue and fevery sensations with aches.

[SofiaDeo in reply to Rando21]

Tagamet/cimetidine was mentioned in the stuff I was browsing yesterday. But there might be a problem for certain patients. While the med solo may work:

pubmed.ncbi.nlm.nih.gov/349...

There is an problem with at least one small molecule kinase inhibitor (dasatinib) and acid suppressing agents, such that the blood concentration of the dasatinib was reduced because absorption was impaired in at least some patients. Cimetidine itself wasn't used, it was famotine, nizatidine,and the proton pump inhibitor lansoprazole.

pubmed.ncbi.nlm.nih.gov/221...

So the situation seems complex. I'll mention that when looking at the drug classes that ibrutinib was tested against for drug interactions, I was seeing data about med classes that mostly affect the various liver enzymes, and I *wasn't* seeing where ibrutinib was tested against the H2 blocker drug class, which seems odd. Unless someone somewhere figured out that dasatinib, being a "broad" kinase inhibitor, was having that effect because of kinases other than BTK. And I am just not able to find that data right now. Or I am just not finding it, lol

To further complicate this issue, there appears to be some data claiming (I haven't assessed the studies but the journal is a reputable one) that dasatinib side effects were *reduced* using these agents. So, there is an interaction, but it's being used successfully to mitigate effects of another agent. We see a drug used this way with ritonovir (originally used to potentiate HIV agents, now one of the 2 agents in Paxlovid).

link.springer.com/article/1...

So IMO the takeaway is, even if it's OTC, if you want to use these med combinations, just do it with the doctor monitoring for effects and don't be constantly stopping/starting the cimetidine or whatever. You don't want to have *you* be one of the patients that gets a dramatic increase in the cancer med and adverse effects from rapidly increased blood levels, after suddenly stopping an H2 blocker.

researchgate.net/publicatio...

[Rando21 in reply to SofiaDeo]

Fortunately I’m still in watch and wait. I will defiantly keep this in mind. Thanks

[Pearlpink]

sorry - I think this was the research I saw when I decided to try loratadine again.

mdedge.com/hematology-oncol...

[Pearlpink]

I remember something about Tagamet but can’t remember where!

[morepork]

I've been taking loratadine OTC for some years for an increased watery rhinitis , sneezing and itchy eyes . Like a perpetual hayfever. As those symptoms developed after starting Ibrutinib I did wonder if the BTK inhibitor might have been the cause - but reading other responses it appears not, and may even be beneficial. 😊