66. How long does it take to react to a trigger?
There isn’t a straight answer to this. The time it takes to react to a trigger is hugely variable. It depends upon the trigger; the strength of the reaction it triggers; the patient; the medications they take; their lifestyle; and other activities that may increase or decrease reactivity. As we have discussed before, the reaction you see from a trigger is often the cumulative result of how much histamine you have circulating at the time, which can be affected by many other things. Reactions can happen immediately or several days later. It is not unusual for mast cell patients to react days later, especially to things they have ingested. This logically makes sense to me as a result of the trigger still being in the GI tract but there is still not definitive proof that explains why you can react days later.
67. What physical things trigger mast cells?
A lot of physical things trigger mast cells. The exact reasoning for why some of these things trigger mast cells is still not well understood. However, these triggers are documented in literature, often as triggers for physical urticaria (hives caused by physical triggers) and/or angioedema (swelling). While reactions to these triggers often start in the skin, the mast cell activation can spread to other mast cells elsewhere in the body. Additionally, patients may not have skin symptoms but have reactions to the following triggers.
Heat and cold can both activate mast cells. Hot water and cold water are both common triggers. Water in general is a trigger for some. Emotional stress is activating, as is various forms of physical stress, including exercise, surgery, physical trauma, infection, or increased activity of another disease. Sweat can be a trigger, regardless of whether the patient is sweating from exercise, heat, or something else. Pressure on the body, even mild pressure, can cause mast cells to release chemicals. Sunlight and vibrations are also known triggers. Mast cell patients are recommended to premedicate before any medical procedure, including imaging like ultrasounds, X-rays or MRIs, as patients have reported activation from these things. Changes in barometric pressure, such as from a change in weather or a storm, are often reported by patients to cause symptoms.
For more detailed reading, please visit the following posts:
Chronic urticaria and angioedema: Part 2