MCAS
Treatments for Lowering Histamine and Reducing MCAS Symptoms
Dr. Bruce Hoffman
March 4, 2024

Treatments for Lowering Histamine and Reducing MCAS Symptoms

Now, you might be thinking, “Why can’t I just take an antihistamine?”

Antihistamines don’t actually reduce histamine release. They only block histamine receptors, preventing you from feeling the symptoms. You may need a round-the-clock blockade of the H1 and H2 receptors, every 12 hours.

If you want lasting relief for MCAS:

  • Histamine 1 blockers – hydroxyzine, doxepin, loratadine, fexofenadine, diphenhydramine, ketotifen, and cetirizine.
  • Histamine 2 blockers – famotidine (Pepcid, Pepcid AC), cimetidine (Tagamet, Tagamet HB), ranitidine (Zantac). Famotidine is chosen most often as it has fewer drug interactions than Tagamet).
  • Mast cell stabilizers – cromolyn, ketotifen (both a mast cell stabilizer and an H1 blocker), hydroxyurea, quercetin.
  • Leukotriene inhibitors – montelukast (Singulair), zafirlukast (Accolate)
  • Tyrosine kinase inhibitors.

H1 and H2 histamine blockers must be taken every 12 hours for maximum effect. It may take up to 12 months to achieve maximum therapeutic effect. The doses may need to be increased to up to three times the recommended over-the-counter dosing.

Here is how I approach treatment with my MCAS patients:

  • Eat a low-histamine diet: Remove alcohol, smoked and cured meat, tinned fish, pickled and fermented foods, berries (strawberries being one of the worst culprits), citrus, nuts, chocolate, dairy, spinach, yeast, soy sauce, tomatoes and tomato products, preservatives, and vinegar. Stop eating leftover food. This will only reduce the incoming histamine and won’t affect the mast cell overactivity within the cells of the body. A comprehensive guide regarding the low-histamine diet can be found here.
  • Promote good gut health: Cut back on gut-damaging and inflammatory foods, and increase probiotics. Use a DAO enzyme, which goes under the generic name Umbrellux DAO – two tablets, 20 minutes before each meal.
  • Stabilize mast cell release of histamine with quercetin and vitamin C 500 mg – two tablets three times daily. We use a product called Natural-D Hist from Ortho Molecular Products.
  • Use H1 and H2 blockers every 12 hours – I use, on average, levocetirizine 5 mg twice daily and famotidine 20 mg twice daily.
  • Block nighttime histamine release with ketotifen or zaditen – 0.25–1 mg at night. Excellent sleep aid, mast cell stabilizer, H1 antihistamine. Excellent treatment for eosinophilic esophagitis.
  • Treat any existing infections: Have a thorough examination done to identify and treat any potential infections in the body which are powerful mast cell triggers. Stool testing by Genova labs and Cyrex Lab Pathogen Testing (array 12) can be of assistance in identifying pathogens.
  • Identify and remove toxins and allergens: This could be heavy metals, mercury fillings, cosmetics, and household cleaners.
  • Nutrients that assist in the treatment: This includes vitamin B6, alpha lipoic acid, vitamin C and E, selenium, omega-3s, N-acetylcysteine (NAC), methylation donors like methyl-folate, SAMe, and riboflavin.
  • Herbs: Nigella sativa, butterbur, turmeric, ginger and peppermint.
  • Get into a solid routine: Getting high quality sleep and staying on schedule helps keep mast cells in check.
  • Reduce stress: Stress, through the action of corticotropin hormone, can activate your mast cells and cause them to destabilize and release mediators.
  • One of the best resources for how to deal with histamine and mast cell activation through nutrition and supplementation is the website and Facebook posts by Yasmina Ykelenstam www.healinghistamine.com.

It can be incredibly discouraging to feel so sick for so long and not find any answers. It is my hope that we continue to learn more about multisystem conditions such as MCAS and spread useful information so it may end up in the hands of those suffering.

Share this article with friends and family to help spread the word about mast cell activation syndrome and histamine blockers. They may discover it’s more than allergies that’s keeping them down.

Dr. Bruce Hoffman

Dr. Bruce Hoffman, MSc, MBChB, FAARM, IFMCP is a Calgary-based Integrative and Functional medicine practitioner. He is the medical director at the Hoffman Centre for Integrative Medicine and The Brain Centre of Alberta specializing in complex medical conditions.

He was born in South Africa and obtained his medical degree from the University of Cape Town. He is a certified Functional Medicine Practitioner (IFM), is board certified with a fellowship in anti-aging (hormones) and regenerative medicine (A4M), a certified Shoemaker Mold Treatment Protocol Practitioner (CIRS) and ILADS trained in the treatment of Lyme disease and co-infections.

He is the co-author of a recent paper published by Dr. Afrin’s group: Diagnosis of mast cell activation syndrome: a global “consensus-2”. Read more about Dr. Bruce Hoffman.