SILVER SPRING, Md., Sept. 2 (UPI) -- The Food and Drug Administration recently issued warning letters to five distributors of powdered caffeine products because of confusing, misleading, or potentially dangerous instructions on their labels.
The letters follow the deaths of two otherwise healthy teenagers in 2014 after consuming caffeine supplements.
"While consumers of caffeinated products such as coffee, tea, and soda may be aware of caffeine's less serious effects -- such as nervousness and tremors -- they may not be aware that these pure powdered caffeine products are much more potent and can cause serious health effects," the agency wrote in a press release.
After the two young men's deaths, the FDA issued a consumer safety alert in 2014 about pure powdered caffeine sold in bulk bags over the Internet, saying at the time that "pure caffeine is a powerful stimulant and very small amounts may cause accidental overdose. Parents should be aware that these products may be attractive to young people."
All the companies' products list "caffeine anhydrous" as their sole ingredient and are sold as health supplements. The agency deemed the products to be "adulterated" under federal law, which requires the FDA to monitor "dietary supplements that present a significant or unreasonable risk of illness or injury under the conditions of use recommended or suggested in the labeling."
In all the listed products, serving sizes are listed as between 50 mg and 200 mg. In addition to the agency's concerns about the dosage suggested for the products, all of the labels indicate imprecise measurements, raising the potential for accidental overdoses. This included what the agency saw as an inability of the average consumer to measure powder in the way the companies suggest.
For example, the label on Hard Eight Nutrition's "Caffeine Powder" product lists three suggested servings -- one-sixteenth of a teaspoon for 189 mg of caffeine, one-eighth teaspoon for 378 mg, and 1/4 teaspoon for 756 mg. FDA notes in its letter that the amounts of caffeine for one-eighth and one-quarter teaspoon is more than the suggested serving on the package.
FDA also noted in the letter to Hard Eight that many consumer measuring cup sets do not include a measurement for one-sixteenth of teaspoon, and even if they did, the dose would be difficult to properly measure because of the differences in how tightly packed powder may be when scooped.
The concerns raised in the letter to Hard Eight are specific to their products, however similar descriptions and concerns can be found in each of the letters. Differences were specific to each regarding suggested servings and measurements of powders.
A single teaspoon of pure caffeine is equivalent to about 28 cups of regular coffee, which is much more than any person is recommended to take. The symptoms of caffeine overdose can include rapid or dangerously erratic heartbeat, seizures, vomiting, diarrhea, stupor and death.
Each of the companies was given 15 days to respond to the letters.