: an abnormal condition caused by the consumption of large amounts of caffeine and marked by restlessness, nervousness, irritability, insomnia, diuresis, tremors, and tachycardia
In general, more than 1.5 grams of caffeine a day can cause the typical symptoms of caffeinism: anxiety, insomnia, irritability and palpitations.—
Richard A. Friedman, The New York Times
Richard A. Friedman, The New York TimesI ran in to find her pale, in a cold sweat, with her heart racing. She had had four cups of coffee in two hours and was suffering from caffeinism.—People Weekly
People WeeklyCite this Entry
“Caffeinism.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/caffeinism. Accessed 30 Oct. 2025.
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