Kate’s Top OTC Mast Cell Stabilizers & Antihistamines
The Mast Cell Stabilizers That Helped Me Navigate Gadolinium Toxicity
When I first started experiencing symptoms of gadolinium toxicity, I had no idea mast cell stabilizers could help. In fact, it took me years to even learn what they were! I had no idea that my symptoms of burning tissues, erratic heart rhythms, excess burping, chest pain, and cognitive dysfunction, all clear signs of an immune response to gadolinium, could actually relate to the mast cell. Damn mast cells! Too bad you need those guys to survive ;)
While mast cell activation isn’t the only issue at play with gadolinium toxicity (we're talking mineral displacement, tissue damage, hypoxia, neurotoxicity, excitotoxicity, T-cell dysfunction, and more), it definitely contributes to some of the most persistent and consistent flares. In my opinion, the only true way to know if you are dealing with mast cell is to take the medications that treat it and see if you get some relief… Through a process of trial and error (accidentally reducing my stomach acid with pepcid - no thanks), I discovered a stack of supplements and medications that made bigger difference than steroids ever did.
Below is a list of mast cell stabilizers and antihistamines I’ve tried, what they’re used for, how they’re tolerated by many people (including myself), and links if you want to try them yourself. Everyone’s body is different, so what didn’t work for me might work beautifully for you, and vice versa.
To hear me talk about this experience, watch this video. Although I obviously cannot give medical advice, I do think it would be beneficial to take mast cell stabilizers as soon as possible with gadolinium. That means, if you are chelating in three months, start now because a few weeks-months of mast cell stabilization will mean that your body is even more prepared and calmer with hopefully(!) a lower flare down the line when you start DTPA.
🌿 Mast Cell Stabilizers & Antioxidants to Explore
1. Liposomal Quercetin (Natural Factors)
This is one of the supplements I felt a distinct day and night difference with, but granted, I was in a HUGE flare when I first tried it. Mast cell stabilizers are gentle and work by building up in the body, so it may take days to notice that you a gentle effect like less flares overall, as opposed to them being an emergency med that kicks in after the fact. Liposomal formulations are generally better absorbed, and this one includes a hint of peppermint oil, which sounds small, but somehow made the experience gentler and more enjoyable.
I also tried a different brand of quercetin and felt nothing, so I cannot personally recommend anything other than this exact product from Natural Factors because it’s so much more effective.
Note: Quercetin can chelate iron, so if you have low ferritin or iron issues, consider cycling it or monitoring levels.
2. Superoxide Dismutase (SOD)
SOD is a powerful antioxidant enzyme that your body makes to neutralize oxidative stress. This supplement uses melon pulp as a natural source. It helped particularly during extreme flares, when my tissues felt hot, painful, and inflamed. It's also thought to stabilize mast cells, which adds to its benefit profile.
Bonus: I experienced no side effects from this at all. It felt more like taking a food than a drug.
3. PEA (Palmitoylethanolamide)
PEA is a naturally occurring fatty acid that supports nerve health and may modulate mast cell activity. It is the supplement that Talia Smith mentioned that she recently started using in our most recent interview. I didn't experience noticeable changes when taking it, likely because I added it in later alongside other treatments. However, others swear by it for allergic and inflammatory symptoms. My doctor also recommended it.
Many people pair it with Luteolin, another flavonoid-based mast cell stabilizer. That said…
4. Luteolin
I personally didn’t tolerate Luteolin only because it seemed to aggravate my digestive issues, possibly due to mild antimicrobial properties. But others find it helpful for stabilizing mast cells and reducing histamine-related symptoms. If you try it, consider testing it alone (not combined with other supplements) to assess your individual reaction.
5. Curcumin / Turmeric
Turmeric is well-known for its anti-inflammatory properties, and curcuminoids may also have mast cell–stabilizing effects. I found that turmeric didn’t reduce inflammation by itself in the middle of a flare, but when taken alongside something stronger, it helps prolong the anti-inflammatory effects.
In my experience, it was useful during tapering periods to extend relief windows.
💊 Over-the-Counter Antihistamines That Helped
6. Claritin (Loratadine, Generic)
This one was a game-changer. I experienced cardiac symptoms post-gadolinium, tachycardia, arrhythmia, chest pain, and Claritin helped regulate those episodes. It’s thought that mast cells in the heart are involved, and suppressing their activity brought real relief.
It’s non-drowsy, non-anticholinergic, and doesn’t cross the blood-brain barrier, which means it won’t impair cognition like Benadryl can. (FYI: Long-term use of Benadryl has been associated with increased dementia risk. I reacted horrifically to benadryl after gadolinium.)
Claritin brand 30ct | Claritin brand 100ct
7. Allegra (Fexofenadine)
Another non-drowsy antihistamine that I take occasionally during severe episodes. Like Claritin, it doesn’t cross the blood-brain barrier and offers gentle symptom relief without sedation or cognitive fog. I like this one as much as I like claratin!
Allegra generic | Allegra brand
7. Astepro - Nasal Spray
This is the only nasal spray I’m willing to use, aside from NasalCrom, which is a prescription form of sodium cromolyn designed for nasal use. As far as I could find, Astepro is the only over-the-counter antihistamine nasal spray currently available. Every other option I reviewed came with side effects I’m not willing to risk, including increased vasoconstriction and steroids.
WHY ARE SO MANY NASAL SPRAYS STEROIDS? At this rate, we’re heading toward a weak-boned society.
Astepro isn’t perfect. It tastes terrible if it drips down your throat, and it can sometimes cause a bloody nose (which I’ve never had from it but I am judicious with the sprays). Compared to everything else out there, those are the most tolerable side effects I found.
I had never used a nasal spray in my life before gadolinium toxicity. But now, in emergency situations where I’m at risk of anaphylaxis, it’s one of the few tools I have to intervene fast.
Thanks, gadolinium 🙃
⚠️ The Ones I Don’t Like (for myself)
Pepcid (Famotidine) – Often recommended for histamine control (as an H2 blocker), but it lowers stomach acid, which made it a disaster for my already low stomach acid and intestinal microbial overgrowth.
Montelukast / Singulair – I have heard this can be extremely helpful, as it is a leukotriene receptor antagonists. However, it carries a black box warnings because so many people had personality changes on it, particularly children. Now that I think of it, I’ll keep my personality and my scorching tissues, thanksomuchthough!
Benadryl (Diphenhydramine) – Crosses the blood-brain barrier and is anticholinergic, which can contribute to cognitive decline. I took it once recently for my throat closing up because I HAD TO, and it’s taken months for my brain to bounce back. I was tremoring and forgetting everything, but it technically did keep me breathing.
Zyrtec / Xyzal - Some people claim that Zyrtec helps them with their gadolinium symptoms, but there was recently a warning about using Zyrtec longterm and a possible withdrawal effect from it, including rebound symptoms. For some reason, Zyrtec & Xyzal both gave me excruciating bone pain, which I have never experienced with any other mast cell medication so far. Xyzal is Zyrtec’s cousin.
Final Thoughts
I still have symptoms, and I hope to explore other MCAS healing strategies like nervous system retraining. But these stabilizers have helped me avoid full-on episodes that can be extremely debilitating without medication.
If you’re just starting to explore mast cell stabilization, I highly recommend introducing one supplement at a time, ideally with as few filler ingredients as possible. This helped me isolate which things were actually helpful vs. problematic.
FEEL BETTER! If you want to buy these supplements, I have attached affiliate links to this article, but I get 1% of the sale, which is probably literally pennies, so just buy wherever it’s cheapest for you! And if you save $5 from doing so, consider donating to the website.
Kate
