Health Library Explorer
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A-Z Listings Contact Us
Click 'Back to Intro' to return to the beginning of this section.

Idiopathic Environmental Intolerance (IEI)

What is IEI?

Idiopathic environmental intolerance (IEI) is a set of symptoms caused by contact with some kinds of substances. It used to be known as multiple chemical sensitivity (MCS). People with IEI have symptoms when exposed to low levels of common substances. Symptoms can include fast heart rate, sweating, and feeling dizzy.

What causes IEI?

Researchers are doing studies to learn the causes of IEI. It's not an allergic reaction. It does not cause the release of chemicals by the immune system. A physical cause is hard to find. Because of this, some studies suggest IEI may be linked to psychiatric disorders. These include somatoform disorders, depression, and anxiety. IEI occurs more often in women than in men. IEI happens more often in people in their 30s or 40s.

Triggers

Substances that cause symptoms are called triggers. These may be synthetic or natural substances. Reported triggers include:

  • Caffeine

  • Food additives

  • Carpet and furniture odors

  • Perfumes and scented products

  • Paint

  • Cigarette smoke

  • Vehicle exhaust, fuel odors

  • Pesticides and herbicides

  • Mobile telecommunication devices

Symptoms

People with IEI may have symptoms such as:

  • Increased heart rate, palpitations

  • Chest pain

  • Sweating

  • Shortness of breath

  • Fatigue

  • Dizziness

  • Warmth and redness of the face and neck (flushing)

  • Nausea

  • Trouble concentrating

  • Cough

  • Numbness

Treatment

Treatment for IEI may include:

  • Staying away from triggers

  • Counseling that may include cognitive behavioral therapy (CBT)

  • Medicines for some symptoms

Online Medical Reviewer: Deborah Pedersen MD
Online Medical Reviewer: Marianne Fraser MSN RN
Date Last Reviewed: 2/1/2024
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
Powered by StayWell
About StayWell | Disclaimer | Terms of Use

Our web site is designed to provide general information to educate users about programs and services, which may be available through our hospitals. The web site is not intended to provide medical advice nor should the information be used to attempt to determine the presence, absence or severity of any illness or medical condition which may be perceived or experienced by the user of this site. If you have or suspect you may have an illness or condition which you believe requires medical attention, we recommend you call your primary care physician. If you believe you are experiencing a medical emergency please call "911" (or your local medical emergency number) or seek immediate care from the nearest hospital Emergency Department. The provision of information to users of this web site is not intended as an inducement or to otherwise influence a person's decision to order or receive any item or service from a particular provider, practitioner or supplier that is reimbursable under Medicare, a state healthcare program (e.g., AHCCS) or any other healthcare plan.

Physicians are members of the medical staff at each facility, but are independent contractors who are neither employees nor agents of Tenet Florida Coastal Division; and, as a result, Tenet Florida Coastal Division is not responsible for the actions of any of these physicians in their medical practices.