TABLE 2

Common Ingredients, Therapeutic Uses, and Adverse Effects of Energy Drink Ingredients8,14,25,30,49,53,82,83

IngredientDescriptionTherapeutic UsesPurported Effect From Energy DrinksAdverse Effects (due to Idiosyncratic Reaction or Excessive Dosage)
CaffeineAn adenosine receptor antagonist: a central nervous system stimulantAs caffeine citrate, used to treat apnea and bronchopulmonary dysplasia in premature infantsIncreases exercise endurance and improves cognition and mood when fatigued or sleep-deprivedNervousness, irritability, anxiety, insomnia, tachycardia, palpitations, upset stomach, vomiting, abdominal pain, rigidity, hypokalemia, altered consciousness, paralysis, hallucinations, increased intracranial pressure, cerebral edema, seizures, rhabdomyolysis, supraventricular and ventricular tachyarrhythmias
GuaranaA South American plant that contains large amounts of caffeine, theobromine, and theophylline (a chronotrope and an inotrope) and tanninsNone knownStimulant, mainly through the effects of caffeine, and weight lossGenerally considered safe by the FDA Center for Food Safety and Applied Nutrition
TaurineAn abundant amino acid in the central nervous system; acts in neural growth and protection, cell metabolism, osmoregulation, antioxidation, and glycolysis; estimated daily intake is 400 mg/dInfant formula has been supplemented with taurine since the 1980s because of evidence that it promotes healthy development; used to treat alcohol withdrawal, congestive heart failure, cystic fibrosis, palpitations/dysrhythmias, hypertension, diabetes, seizure disorders, hepatitisMarketed to promote eye and biliary health and to prevent congestive heart failure by lowering blood pressure while improving cardiac contractilityGenerally considered safe by the FDA
l-CarnitineAn amino acid involved in β-oxidation of fatty acidsUsed as a therapeutic supplement in congenital and acquired-deficiency states, end-stage renal disease, valproate toxicity, and dementia; increases attention and decreases hyperactivity in certain populations of children; nonstimulant l-acetyl-carnitine is used to treat ADHD in boys with fragile X syndrome and, in 1 study, children with typical ADHD; it may also protect against heart diseaseAdded to promote fat metabolism and increase enduranceIn high doses, can cause nausea, vomiting, abdominal pain, and diarrhea; has been reported to cause seizures in patients with no known disease and to increase seizure frequency in patients with seizure disorder
GinsengAn East Asian herbBelieved to improve memory, increase stamina, and stimulate immune functionImprove physical performanceReported symptoms of ginseng toxicity include diarrhea, vaginal bleeding, headache, vertigo, mania, hypertension, rashes, insomnia, irritability, Stevens-Johnson syndrome, and agranulocytosis; some of these symptoms may be related to contaminants, such as phenylbutazone and aminopyrine, used in its processing
YohimbineAn alkaloid found in the plants Pausinystalia yohimbe and Rauwolfia serpentinaAn herbal supplement believed to be an aphrodisiac and to relieve chest pain, diabetic complications, depression, and erectile dysfunctionIncrease energy, metabolism, and stamina; promotes well-beingCan cause hypertension at usual doses and hypotension at high doses; tachycardia, death