Carson Meyer had been feeling perpetually tired for almost a year.
The 20-year-old, who had recently been drafted by the Columbus Blue Jackets hockey team, had been experiencing relentless lethargy along with pale skin and a loss of appetite.
Doctors, psychiatrists and trainers thought the Powell, Ohio, native might have depression, mononucleosis, and even cancer.
It wasn't until a trip to the bathroom that Meyer figured out why he was sick - a 25-inch tapeworm had been living in his small intestine.
Hockey player Carson Meyer, 20 (left and right, with his mother), from Powell, Ohio, had been experiencing relentless lethargy along with pale skin and a loss of appetite for almost a year. What he believed was a serious disease was actually a tapeworm living in his small intestine
The college sophomore, recently drafted by the Columbus Blue Jackets (pictured), was thought to be suffering from depression, mononucleosis and even cancer
Meyer told The Athletic he had been feeling sluggish throughout the summer after completing his freshman year at the University of Miami in Oxford, Ohio.
He had just been selected in the sixth round of the 2017 NHL Draft for the Blue Jackets and he hoped that getting back into the swing of classes would help with his lethargy.
But it didn't and, as winter rolled around, Meyer suffered from a loss of appetite, he dropped weight and he would fall asleep during drills.
Tapeworms have evolved specialized 'heads' that carry an arsenal of spines or retractable hooks to attach themselves to the intestines of their hosts.
These parasites don't have a gut of their own. Instead, they use their outer surface to absorb nutrients and excrete waste.
Beyond the 'head' and 'neck,' areas, a tapeworm is just a series of segments, each with its own male and female sexual parts. Eventually, they mature and make eggs.
Tapeworms infest a wide variety of animals. Whales get tapeworms, and in these huge mammals the parasites can grow to 100 feet or more.
If left untreated in humans, the patient's life may be in danger as the infestation can affect key areas of the intestine.
His performance began to suffer as well. Meyer went from scoring 26 points in 32