Health Encyclopedia

Methadone overdose

Definition

Methadone is a very strong painkiller. It is also used to treat heroin addiction. Methadone overdose occurs when someone accidentally or intentionally takes more than the normal or recommended amount of this medicine. This can be by accident or on purpose.

Methadone overdose can also occur if a person takes methadone with certain painkillers. These painkillers include oxycontin, hydrocodone (Vicodin), or morphine.

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 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

Methadone can be poisonous in large amounts.

Where Found

Medicines with these brand names contain methadone:

• Dolophine
• Methadose
• Physeptone

Other medicines may also contain methadone. The ones above include methadone products that are swallowed or injected into a vein, muscle, or under the skin.

Symptoms

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

EYES, EARS, NOSE, AND THROAT

• Tiny pupils

STOMACH AND INTESTINES

• Constipation
• Nausea and vomiting
• Spasms of the stomach or intestines

HEART AND BLOOD

• Low blood pressure
• Weak pulse

LUNGS

• Breathing problems, including slow, labored, or shallow breathing
• No breathing

NERVOUS SYSTEM

• Coma (decreased level of consciousness and lack of responsiveness)
• Confusion
• Disorientation
• Dizziness
• Drowsiness
• Fatigue
• Muscle twitches
• Weakness

SKIN

• Blue fingernails and lips
• Cold, clammy skin

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 medicine (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 your vital signs, including temperature, pulse, breathing rate, and blood pressure.

Tests that may be done include:

• Blood and urine tests
• Chest x-ray
• CT scan
• ECG (electrocardiogram, or heart tracing)

Treatment may include:

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

Outlook (Prognosis)

How well someone does depends on the amount of poison swallowed and how quickly treatment is received. The faster medical help is given, the better the chance for recovery.

If an antidote can be given, recovery from an overdose begins right away. However, since methadone's effects can last for about a day, the person often stays in the hospital overnight. They may receive several doses of the antidote.

People who take a large overdose may stop breathing. They may have seizures if they do not get the antidote quickly. Complications such as pneumonia, muscle damage from lying on a hard surface for a long time, or brain damage from lack of oxygen may cause permanent disability.

Death can occur in severe cases.

References

Aronson JK. Opioid receptor agonists. In: Aronson JK, ed. Meyler's Side Effects of Drugs. 16th ed. Waltham, MA: Elsevier; 2016:348-380.

Kowalchuk A, Reed BC. Substance use disorders. In: Rakel RE, Rakel DP, eds. Textbook of Family Medicine. 9th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 50.

Nikolaides JK, Thompson TM. Opioids. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 156.

Welsh C, Chang J. Opioid overdose. In: Johnson BA, ed. Addiction Medicine: Science and Practice. 2nd ed. Philadelphia, PA: Elsevier; 2020:chap 54.

Review Date:11/13/2021
Reviewed By:Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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