Can Pistachio Nuts Cause Diarrhea?

Pistachio nuts do not commonly cause diarrhea but if you develop diarrhea after eating pistachio nuts, you may have an allergy. The Food Allergy and Anaphylaxis Network states, that more than 1.8 million Americans suffer from a tree nut allergy 1. Pistachio nuts are a tree nut that can cause common gastric symptoms, such as diarrhea, nausea and abdominal cramping. If you suspect that you have an allergy to pistachio nuts, call your doctor. Stop eating pistachios until you are able to be evaluated.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.


Pistachios are considered a tree nut, among hazelnuts, walnuts and almonds. If you’re allergic to one tree nut, you are at high risk of having an allergy to other tree nuts, according to the Food Allergy Initiative. Tree nut allergies are one of the most common food-related allergens among adults that could be a life-long condition, according to the Food Allergy and Anaphylaxis Network 1.


During an allergic reaction to pistachios, the immune system malfunctions and mistakes the proteins in the nut as a harmful substance. Kids Health explains that the immune system builds a defense system against the proteins by producing specific antibodies call immunoglobulin E, or IgE. IgE antibodies cause mast cells in the gut to produce histamine. Histamine assists the body fight off infection, but in high amounts, it causes inflammation. Inflammation and swelling in the intestines can lead to diarrhea and other gastrointestinal complications.


Gastrointestinal symptoms include:

  • vomiting
  • diarrhea
  • nausea
  • abdominal pain
  • cramping
  • gas

If you’re allergic to pistachios, you will develop other symptoms alongside having diarrhea.


Treatment begins with a proper diagnosis. Talk with an allergist about undergoing testing to confirm an allergy to pistachios. If diagnosed, avoid the consumption of all tree nuts. The Food Allergy Initiative states that the Federal Government requires that all food manufactures disclose the use of tree nuts on their packaging. Read all ingredients and when eating out, ask your server to avoid tree nuts.


Diarrhea can lead to weight loss, dehydration and malnourishment. Use electrolyte sports drinks to maintain proper hydration until you can be seen by your doctor.