The 57-year-old, from Alabama, was hospitalized feeling shaky, with tingling and numbness in his right arm and leg.
A CT scan revealed he had suffered a small but life-threatening brain hemorrhage.
Surgeons at the University of Alabama at Birmingham stroke center managed to treat the unidentified man’s symptoms.
However, he continued to report tingling, numbness, and shakiness months after his attack, according to the report published on Wednesday in the American Journal of Emergency Medicine.
The author, Dr Anand Venkatraman, warns the incident should be a warning sign to energy drink consumers that our brains struggle to cope with such high levels of caffeine and supplements that send blood pressure rocketing.
‘The man reported that his symptoms began about 15 minutes after drinking an energy drink, the first time he had consumed this particular product, as he was about to do yardwork,’ Dr Venkatraman, a fourth-year resident in the Department of Neurology at UAB, said.
Dr Venkatraman says the drink contains a high level of caffeine, along with a variety of other ingredients, many of which are associated with increases in blood pressure.
‘This particular drink contains several supplements for which we have little understanding of their potential interactions with each other or with caffeine,’ Dr Venkatraman said.
‘One is structurally similar to amphetamines, and several are known to stimulate the sympathetic nervous system.’
The sympathetic nervous system regulates what is known as the ‘flight or fight’ response.
When faced with an urgent, potentially dangerous situation, the body gears up to either take extraordinary action (fight) or run away (flight).
‘The body begins to marshal all of its resources to respond to the situation at hand—boosting strength and alertness, for example—in part by raising blood pressure to increase blood flow,’ Dr Venkatraman said.
‘For a patient who may be at risk for vascular disease, this increase in blood pressure could be potentially dangerous, as a rise in blood pressure can affect an already weakened blood vessel to the point that it ruptures.’
Ingredients in the drinks that are suspected to influence the sympathetic nervous system include yohimbine and green tea extract.
‘These ingredients are supplements and, as such, are not regulated by the government to the same degree that medications are,’ Venkatraman said.
‘We don’t have good information on dosing for some of these supplements. We don’t know how much is too much, for example, especially in populations with varying degrees of risk.’
Another issue is serving size. The manufacturer’s label says the bottle contains two servings, but the patient reported that he drank the full 8 oz. bottle at one time, a behavior that Dr Venkatraman believes is common.
‘The warning here is that we do not fully understand how some of these ingredients interact with other compounds,’ Dr Venkatraman said.
‘Nor do we have enough information on maximum dosages, especially for individuals with underlying health issues.
‘Consumers need to be aware of the ingredients in the drinks if they choose to use them, and check with their physician if they have questions. They should also follow the manufacturer’s recommendations.’
In this case, the patient had a history of elevated blood pressure and was at increased risk for vascular disease.
‘I am not anti-energy drink,’ Dr Venkatraman said.
‘In fact, I use them myself on occasion. But I strongly urge consumers to read the label and be informed. Don’t take unnecessary risks with your health. There is potential for a serious outcome.’