An overdose is when you take more than the normal or recommended amount of something, usually a drug. An overdose may result in serious, harmful symptoms or death.
If you take too much of something on purpose, it is called an intentional or deliberate overdose.
If the overdose happens by mistake, it is called an accidental overdose. For example, a young child may accidentally take an adult's heart medicine.
Your doctor may refer to an overdose as an ingestion. Ingestion means you swallowed something.
An overdose is not the same as a poisoning, although the effects can be the same. Poisoning occurs when someone or something (such as the environment) exposes you to dangerous chemicals, plants, or other harmful substances without your knowledge.
An overdose may be mild, moderate, or serious. Symptoms, treatment, and recovery depend on the specific drug involved.
In the United States, call 1-800-222-1222 to speak with a local poison control center. This hotline number will let you talk to experts in poisoning. They will give you further instructions.
You should call if you have any questions about an overdose, poisoning, or poison prevention. You can call 24 hours a day, 7 days a week.
At the emergency room, an examination will be performed. The following tests and treatments may be needed:
Airway support, including oxygen, breathing tube through the mouth (intubation), and breathing machine (ventilator)
Blood and urine tests
CT (computed tomography, or advanced imaging) scan
EKG (electrocardiogram, or heart tracing)
Fluids through a vein (intravenous or IV)
Medicines to treat symptoms, including antidotes (if one exists) to reverse the effects of the overdose
Kulig K. General approach to the poisoned patient. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 147.
Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.