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Stimulants

Stimulants are chemicals (usually drugs or medicines that increase your heart rate, breathing rate, and brain function. Some stimulants affect only a specific organ, such as the heart, lungs, brain, or nervous system.

Epinephrine is a stimulant. It is given during cardiac arrest to stimulate the heart and help restore the heartbeat.

Other times, stimulants can cause unwanted side effects. For example, pseudoephedrine found in some cold medicines can increase the heart rate. Caffeine, found in many beverages, may also increase the heart rate or cause a tremor.

References

Taber's Cyclopedic Medical Dictionary. 24th ed. Philadelphia, PA: F.A. Davis Company; 2021. www.tabers.com/tabersonline/view/Tabers-Dictionary/762879/all/stimulant. Accessed December 17, 2024.

Review Date 1/1/2025

Updated by: Linda J. Vorvick, MD, Clinical Professor Emeritus, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.