Dr. Mikhail Khvostov, Deputy Director of the Institute of Medicine and Medical Technology at Novosibirsk State University, stated that a high concentration of caffeine in the blood between 80 and 100 mg/L or more is life-threatening.
Khvostov said: "A caffeine concentration in the blood of 80 to 100 mg/L or more is lethal, which is equivalent to consuming tens of grams of pure caffeine powder or a large number of tablets, or about 100 to 150 cups of espresso. Death as a result of drinking regular coffee, even strong coffee, is unlikely because it is impossible to consume this amount of liquid in a short time, in addition to the vomiting reaction."
He added that serious symptoms such as seizures and ventricular fibrillation may appear at concentrations starting from 15 mg/L and above, noting that caffeine affects the nervous system and the endocrine glands that regulate heartbeats, and that an overdose may directly lead to serious heart rhythm disturbances that may be fatal.
He emphasized that adding milk to coffee does not reduce the toxicity of caffeine, but only dilutes its concentration.
The doctor pointed out that there are three categories that are most at risk: athletes, especially bodybuilders who consume high doses with intensive training, patients with mental disorders, especially those with depression, in addition to infants. He noted that teenagers may also be at risk as a result of consuming large amounts of coffee and energy drinks without being aware of the dose, while a child’s body processes caffeine very slowly, as the lethal dose may reach about 35 mg/kg.
Khvostov warned of the interaction of caffeine with some medications, explaining that its toxicity may increase when taken with antidepressants, antipsychotics, and sedatives, as well as with oral contraceptives that slow its elimination from the body.
