Thursday, December 4, 2008
Loop Diuretics and the Williams Brothers
Pat and Kevin Williams (unrelated), standout defensive linemen for the Minnesota Vikings were recently suspended by the NFL (along with four other players) because traces of the loop diuretic bumetanide were found in their urine. Bumetanide is on the list of banned substances because it can be used as a "masking agent" for anabolic steroids. As of today, the suspensions are on appeal.
From a scientific perspective, this all sounds a little shady. Loop diuretics act by restricting how much water and electrolytes your kidneys absorb. As a result, your urine is diluted and copious. The idea with drug masking is that the excess water in the urine will make the concentration of any naughty substances present artificially low. But it's not necessarily an efficacious way of hiding your devious muscle building strategies. It's all based on concentrations and fluid homeostasis. It's like trying to lower your blood alcohol level at a New Year's Eve traffic stop by guzzling 4 gallons of water in 3 minutes.
But why would they guys be on a loop diuretic? The first line of treatment for an African-American male with hypertension is hydrochlorothiazide, a different kind of diuretic. So it can't be because they're treating high blood pressure. No physician would prescribe bumetanide. Loop diuretics are used in heart failure and certain kidney conditions. I have heard of competitive wrestlers use them because of the rapid weight loss (all water) benefit that can be derived. And maybe these 300 lb behemoths need a little help to keep their weight within reasonable parameters.
But it's horribly unsafe. Dropping weight by hamstringing your kidney's ability to manage your total body fluid levels is unnecessarily dangerous. Too much of it can compromise kidney function and lead to eventual kidney failure. Moreover, electrolyte concentrations (especially potassium) get thrown out of whack when you're on a loop diuretic. All it's going to take is some All-Pro tackle dropping dead on a Sunday afternoon from a hypokalemic arrythmia to get everyone's attention.
Bottom line: there's probably no reason to be on bumetanide, it's dangerous, but I doubt it's being used to mask steroids. If a couple guys have to forfeit a few weeks salary because they got caught using it, it's probably a good thing for the players in the league overall. Now if only we can get them to stop shooting themselves in the thigh with illegal handguns....