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What is Mass Cell Activation Syndrome (MCAS)?
MCAS is caused by abnormal mast cells or the abnormal release of chemicals contained within the mast cell.
Mast cells are a normal part of our body’s immune system and help us to fight infection. These cells are often involved in allergic or inflammatory reactions.
When activated they release many chemicals, such as histamines. Histamines create symptoms that we relate to allergic reactions.
How can MCAS affect you?
MCAS occurs when the mast cells within your body don’t function properly.
The most common signs and symptoms are:
- Fatigue
- Dermographism (a condition in which light scratching of the skin causes raised, red lines)
- Pain all over your body (Fibromyalgia)
- Near fainting and fainting
- Headache
- Itching/nettle rash
- Tingling
- Nausea and/or vomiting
- Chills
- Skin swelling, which moves around the body
- Eye irritation
- Breathlessness.
Other signs although less common:
- Variable blood pressure
- Excessive heart rate
- Blocked nose
- Wheezing
- Flushing
- Diarrhoea
- Abdominal cramps.
On rare occasions a severe allergic reaction can occur called anaphylaxis which includes rapid swelling of skin and tissues particularly around the mouth and airways.
What can trigger your symptoms?
Triggers can vary and sometimes it can be difficult to identify the cause. If you do identify a trigger please try to avoid this. Some common triggers are listed below:
- Alcohol
- Heat
- Medication
- Medical procedures
- Wasp/bee stings or insect bites
- Fever or infection
- Exercise
- Physical stimulation (e.g. pressure, friction)
- Emotions/stress
- Foods
- Perfumes
- Bacteria/mould
- Menstrual cycle.
What treatment options are there?
Although there is no permanent cure for MCAS, management of the condition is based on avoiding triggers and medication to control symptoms.
Antihistamines can be used to dampen down the effect of histamine released by the mast cell. You may be asked to start taking a trial of dual antihistamines for three months.
A dual regimen means that you will take two types of antihistamines daily. You will then be reviewed at three months to explore the effects on your symptoms.
Other medication may be used if symptoms are severe.
Do you have any symptoms of MCAS?
If you feel you are being affected by MCAS and you are currently being seen by the Long COVID Service in St Helens, please contact us. If you are not being seen the Long COVID Service please contact your own GP.
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