My experience with Mast Cell Activation Syndrome (MCAS)

Acute mast cell reactions can be triggered by various things and are very challenging for me. Histamine rich food, stress, physical activity, coffee, alcohol, heat or cold and different smells can lead to allergy-like symptoms.

In my case, symptoms can vary from dizziness and vertigo to presyncope. A major issue is the symptom of brain fog, which occurs frequently – even daily. Brain fog feels as if you cannot concentrate well and the easiest tasks (for example 7 + 8) can be difficult. Additionally, nausea and gastrointestinal cramping could accompany those flares and they can put me in bed for days.

Acute mast cell activation episodes often hit me without preparation, and start with flushing, severe nausea, pain in my stomach and the onset of diarrhea. Then, symptoms become worse up to the point where I am suffering from stomach cramping for the next 24 hours. After those episodes my body will be left very weak, my legs will start to cramp, and I will be very exhausted, which makes me sleep up to 12 h during the night. Usually it takes a couple of days until my condition stabilizes again. Nausea is in general the last symptom to disappear. Sometimes, I have months with a random and permanent variety of symptoms without even knowing what caused them.

Especially the gastrointestinal issues limit my everyday life a lot. My stomach decides about how far I can go from my home, what I can eat or if I can eat outside at all. If my condition worsens when I am not at home, I can hardly stand on my feet and need to get back home as soon as possible.

When I was a child, I had no specific problems with eating. Later, as a teenager, I developed some allergies for the first time. Additionally, an „irritable bowel syndrome“ was diagnosed, and I suddenly experienced lots of problems with severe diarrhea and mild eczemas of my skin. I started to take H1 blockers for my allergies when I was around 16 years old, but only during the summer months. The drugs helped with my allergies, but not with any other symptoms.

Extreme mast cell symptoms have developed after infiltration of my neck with lidocaine and cortisol, which makes it likely that mast cells had a role in the onset of my rapid progression in 2010.

Unfortunately, for many patients triggers become more over time – and I am no exception. For example, since a couple of months, I have been reacting badly to ECG electrodes and band aids, which was no issue in the past.

My therapeutic approach consists of a diet that is low in histamine, and mast cell specific medication, such as: Desloratadin (H1 blocker), twice daily; Daosin, before every meal; Ranitidin 1-2 times daily; emergency medication in case a severe allergic reaction occurs. I tolerate all of those quite well. I only noticed a small side effect when I first started Desloratadin: Fatigue. But luckily, my body got used to it. Medication is so important for me, because most of my triggers are random and not avoidable.

One thing that is helpful for me to document and manage my condition is my mast cell diary. I basically write down what symptoms I develop, what found I ate, which medication I took; and that in turn helps me to identify triggers and connect symptoms. Often it is not only one trigger, but more a combination of them, for example, if I eat chocolate on more than one day or similar small sins, my body reaches a point where it cannot handle just the slightest bit of histamine anymore. It is like there was a border that is crossed.

Since I have been taking the H1 and H2 blockers and the Daosin, my gastrointestinal issues have significantly improved. Plus, following my histamine free or low diet plan, the severe stomach cramping does not occur that often, and my quality of life improves.


If you want to learn more about MCAS have a look here.