Definition

Menthol is used to add peppermint flavor to candy and other products. It is also used in certain skin lotions and ointments. This article discusses menthol poisoning from swallowing pure menthol.

This article is for information only. DO NOT use it to treat or manage an actual poison exposure. If you or someone you are with has an exposure, call your local emergency number (such as 911), or your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.

Poisonous Ingredient

Menthol can be harmful in large amounts.

Where Found

Menthol may be found in:

• Breath fresheners
• Candy
• Cigarettes
• Cold sore medicines
• Cough drops
• Creams and lotions to relieve itching
• Gum
• Inhalants, lozenges, or ointments to treat nasal congestion
• Medicines to treat sore mouth, throat, or gums
• Mouthwashes
• Ointments to treat aches and pains (such as Ben-Gay, Therapeutic Mineral Ice)
• Peppermint oil

Other products may also contain menthol.

Symptoms

Below are symptoms of menthol poisoning in different parts of the body.

BLADDER AND KIDNEYS

• Blood in the urine
• No urine output

LUNGS

• Rapid breathing
• Shallow breathing

STOMACH AND INTESTINES

• Abdominal pain
• Diarrhea
• Nausea and vomiting

HEART AND BLOOD

• Pounding heartbeat (palpitations)
• Rapid heartbeat

NERVOUS SYSTEM

• Convulsions
• Dizziness
• Tremor
• Unconsciousness
• Unsteady walking

Home Care

Seek medical help right away. Call poison control for further help.

Before Calling Emergency

Have this information ready:

• The person's age, weight, and condition
• The name of the product (and ingredients and strength, if known)
• Time it was swallowed (or got in the eyes or on skin)
• Amount swallowed (or got in the eyes or on skin)

Poison Control

Your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. This national hotline will let you talk to experts in poisoning. They will give you further instructions.

This is a free and confidential service. All local poison control centers in the United States use this national number. You should call if you have any questions about poisoning or poison prevention. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week.

What to Expect at the Emergency Room

Take the container with you to the hospital, if possible.

The health care provider will measure and monitor the person's vital signs, including temperature, pulse, breathing rate, and blood pressure.

Tests that may be done include:

• Electrocardiogram (ECG)
• Chest x-ray
• Tube down the windpipe and lungs (bronchoscopy) to look for burns and other damage

Treatment may include:

• Fluids through a vein (by IV)
• Medicine to reverse the effects of the menthol and treat symptoms
• Activated charcoal
• Laxative
• Breathing support, including tube through the mouth into the lungs and connected to a breathing machine (ventilator)

Outlook (Prognosis)

How well someone does depends on how much menthol was swallowed and how quickly treatment is received. The faster medical help is given, the better the chance for recovery. Swallowing such poisons can have severe effects on many parts of the body.

Pure menthol is not easy to get. The menthol found in many over-the-counter products is usually watered down and mixed with other ingredients. Therefore, how well a person does also depends on the other ingredients in the product.

References

Aronson JK. Menthol. In: Aronson JK, ed. Meyler's Side Effects of Drugs. 16th ed. Waltham, MA: Elsevier; 2016:831-832.

National Center for Biotechnology Information website. PubChem Compound Summary for CID 1254, Menthol. pubchem.ncbi.nlm.nih.gov/compound/Menthol. Accessed November 23, 2023.