Podcast 1024: Caffeine Toxicity

Contributor: Taylor Lynch, MD

Educational Pearls:

• Excessive caffeine intake can be dangerous.

• For normal adults, the toxicity level starts at 1000mg, which is equivalent to about 10 cups of coffee or 5 celsius drinks. 

• For normal adults, lethal levels are about 5-10 grams, which is equivalent to about 50-100 cups of coffee. Most of these outcomes are not from drinking caffeine, but instead concentrated caffeine pills.

• For children, toxic levels are 15mg per kg of the child. 

 

• Within the last 10 years 20-40 deaths due to caffeine intake have been reported.

• This may be lower than the actual number due to cardiac arrests that potentially could have been caused from caffeine intake. 

 

• Clinical presentation of caffeine toxicity can present in many ways.

• Most common symptoms include agitation and jitteriness

• The far end of the spectrum includes seizures, tachydysrhythmias, and eventually cardiovascular collapse.

 

• Caffeine is a part of the methylxanthine class. 

• Caffeine is a phosphodiesterase inhibitor, which causes the release of calcetamines that act on your beta-2 receptors. This activates the sodium potassium ATPase and causes potassium to shift intracellular. 

• The clinical presentation of this mechanism is a patient with low potassium and agitation.

 

• Treatments for toxic caffeine levels include:

• Replacing potassium, but slowly since the total potassium levels in the body are normal and will eventually return to normal once the caffeine wears off.

• Benzodiazepines

• Activated charcoal

• Dialysis, since caffeine is dialyzable

References

1. National Center for Biotechnology Information. "PubChem Compound Summary for CID 2519, Caffeine" PubChem, https://pubchem.ncbi.nlm.nih.gov/compound/Caffeine. Accessed 9 July, 2026. 

2. Murray A, Traylor J. Caffeine Toxicity. [Updated 2025 Feb 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK532910/

3. Cyril Willson, The clinical toxicology of caffeine: A review and case study, Toxicology Reports, Volume 5, 2018, Pages 1140-1152, ISSN 2214-7500, https://doi.org/10.1016/j.toxrep.2018.11.002.

 

Su