Definition

Peppermint oil is an oil made from the peppermint plant. Peppermint oil overdose occurs when someone swallows more than the normal or recommended amount of this product. This can be by accident or on purpose.

This article is for information only. DO NOT use it to treat or manage an actual overdose. If you or someone you are with has an overdose, 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 is the ingredient in peppermint oil that can be poisonous in large amounts.

Where Found

Peppermint oil is used to flavor various products. It is also used:

• As a germ-killing (antiseptic) product
• As a numbing product (anesthetic)
• In herbal medicine to relieve spasms

Other products may also contain peppermint oil.

Symptoms

Below are symptoms of a peppermint oil overdose in different parts of the body.

HEART AND BLOOD

• Slow heartbeat

LUNGS

• Shallow breathing
• Slow breathing
• Rapid breathing

STOMACH AND INTESTINES

• Abdominal pain
• Diarrhea
• Nausea and vomiting

KIDNEYS AND BLADDER

• Blood in urine
• No urine production

NERVOUS SYSTEM

• Convulsions
• Depression
• Dizziness
• Twitching
• Unconsciousness
• Uncoordinated movement

SKIN

• Redness

Home Care

Seek medical help right away. Do not make the person throw up unless poison control or a health care provider tells you to.

Before Calling Emergency

Have this information ready:

• Person's age, weight, and condition
• Name of the product (ingredients and strength, if known)
• Time it was swallowed
• Amount swallowed

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

Tests that may be done include:

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

Treatment may include:

• Fluids through a vein (by IV)
• Medicine to 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 the amount of peppermint oil swallowed and how quickly treatment is received. The faster medical help is given, the better the chance is for recovery.

Survival past 48 hours is often a good sign that recovery will occur. If the kidneys are damaged, they may take several months to heal. Long-term injury to the lungs can also occur.

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 24, 2023.