Caffeine is a drug that occurs naturally in many plants and can also be produced synthetically. It is a stimulant that acts on your central nervous system, and is used to temporarily increase alertness. Many common beverages and medications contain varying levels of caffeine. According to Mayo Clinic, 8 ounces of coffee contains 150 milligrams of caffeine, 8 ounces of Red Bull has 80mg, 12 ounces of Cola-Cola has 35mg and one NoDoz Maximum Strength pill has 200mg. Caffeine is generally safe in moderate amounts–around 250mg per day for most people-however, too much caffeine can cause short-term physical and psychological side effects, as well as long-term side effects.
Short-Term Physical Effects
Consuming too much caffeine for your body is also known as a caffeine overdose. According to the National Institutes of Health, acute symptoms of caffeine overdose include, but are not limited to: irregular and rapid heartbeat, increased urination, muscle spasms, nausea, vomiting , diarrhea, dizziness and fever. If you or someone you know is experiencing these symptoms and you suspect too much caffeine was consumed, call 911 or the Poison Control Hotline at 1-800-222-1222.
Short-Term Psychological Effects
In addition to physical manifestations, caffeine overdose also causes psychological side effects, since it acts on your central nervous system. Short-term psychological effects of caffeine overdose as reported to the National Institutes of Health include changes in your level of alertness, confusion and hallucinations. These symptoms can be dangerous, and you should also get help immediately if you are experiencing any of them.
Long-Term Effects
Not only can too much caffeine in one dose harm you, but too much caffeine over a long period of time can also be detrimental to your health. A 2004 study published in the Journal of Community Health followed caffeine users over a long period of time. It determined that chronic toxic overdose of caffeine is plausible, and that people who try to stop using caffeine after prolonged use often experience withdrawal symptoms. These withdrawal symptoms are similar to symptoms of acute caffeine overdose, in that they include headache, nausea and anxiety. Too much caffeine can make you dependent on the drug to remain alert, and you may experience feelings of depression and reduced mental acuity if you try to stop using it.
About this Author
Ann Bartkowski is a freelance writer based in San Francisco. She is a dedicated health and science educator who is a regular contributor to the Exploratorium Explainers Blog. She holds a Bachelor of Science in biology from Bates College.
