Signs and Symptoms

Signs and symptoms of the disease vary from person to person and depending on the specific form of systemic mastocytosis (SM). Since histamine and other mediators produced by mast cells are also responsible for allergic reactions, most people with SM experience symptoms that mimic allergies.

In many people, one of the first signs of the disease may include “spots” that look like freckles on the skin and can turn into hives if scratched, irritated or exposed to sudden changes in temperature.

Other common symptoms include:

  • Abdominal pain
  • Anaphylactic shock, or a severe allergic reaction
  • Bloating
  • Bone, joint and muscle pain
  • Diarrhea
  • Difficulty breathing
  • Difficulty concentrating
  • Difficulty sleeping
  • Excessive sweating
  • Itching
  • Fatigue
  • Flatulence
  • Flushing
  • Headache
  • Nausea
  • Skin rashes
  • Swelling
  • Vomiting
  • Weight loss