DALLAS — "I'm sitting there, laying on the bathroom floor, thinking I'm about to die."

Gerrit Choate recounted every detail of a cold winter day in Salt Lake City, Utah.

The worst day of his life.

"The doctor said it was similar to a heroin addict going through a complete cold turkey detox," Choate said.

Gerrit experienced withdrawals for a drug — Luvox, the brand name of fluvoxamine — prescribed to treat obsessive-compulsive disorder (OCD).

"Come to find out from the doctors that the recommended usage is no longer than 30 days, Choate said.

Gerrit's eye widened for emphasis.

"I had been on it for about nine years."

'You tell that kid he can't, and he's gonna do it'

Choate is the son of Southern Methodist University football legend Putt Choate, who still holds the school record for tackles in a season and tackles in a career.

"I grew up going to SMU games," Gerrit said. "It was always a dream to play for SMU."

Dreams turned to nightmares.

In sixth grade, Gerrit broke a bone in his lower back while playing football.

"Several doctors said I was never going to play any sport again," Gerrit said.

Devastating news for a multi-sport athlete.

"You tell that kid he can't, and he's gonna do it," declared his mom Fifi Choate.

After a year in a back brace, Choate consulted with another doctor who told him there's a slight chance he could play again.

Choate adhered to a strict rehabilitation plan and was eventually cleared to play.

The best day of his life.

Obsessive Compulsive Disorder

The Dallas native became an All-State player at Parish Episcopal High School under head coach Scott Nady.

However, the helmet and broad shoulders masked the mental struggles Choate endured for years.

As a child, he was diagnosed with severe anxiety and OCD.

"Suddenly, he became a very anxious little boy," Fifi said. "Always needing reinforcement."

"The best way to describe it is just an overwhelming feeling that if you do don't this task, whatever it is, something bad will happen," Choate said.

The definition of OCD, according to the National Institute of Mental Health, is: a common, chronic, and long-lasting disorder in which a person has uncontrollable, reoccurring thoughts (obsessions) and/or behaviors (compulsions) that he or she feels the urge to repeat over and over. 

"It was kind of difficult for me to understand," Choate's father Putt admitted.

As symptoms worsened, Chaote was prescribed Luvox.

Genetic makeup

With no Division 1 offers out of high school, Chaote walked on at Utah.

However, early into his college career, his mind and body started to shut down.

Doctors recommended Chaote take an expensive drug-gene test.

"Our insurance wouldn't even pay for it," Putt said.

According to the drug-gene test, Luvox was toxic for Choate's genetic makeup.

He had to wean off the drug as soon as possible, which would be no easy task since his body relied on it for nearly a decade.

"'I should've known as a parent.' That's what you beat yourself up the most about," Putt said. "You didn't check. You didn't look. You weren't aware. You didn't protect your child."

Fifi moved out to Utah for a couple of months to help Choate come off the medication. He would take gradually smaller doses until he was off of it completely.

The worst day of his life

One morning, Choate took his daily dose, but he had an upset stomach and vomited.

His body never digested that day's dose.

The worst day of his life.

"It was the most frightening thing I've been through," Fifi said. "He was so violently ill."

"It was just a nightmare," Choate said.

With his mother watching helplessly, Choate vomited 24 times in 12 hours in his Utah dorm.

"It was a complete shock how an anxiety medication could do this to somebody," Choate said. "Because one day off of this stuff has me going through hell."

Over time, Choate weaned off the drug and moved home to Dallas.

He stuck to a strict nutrition plan thanks to his nutritionist Jill Lane and walked on at SMU.

"Most people would've quit," Putt said. "And nobody would've blamed him."

"I just marvel at his determination," Fifi said proudly. "When life keeps knocking him down, there he goes. He's not going to accept it."

Now, Choate sees the benefit to sharing his experience with others.

"He doesn't want another child to go through the hell he had to go through," Fifi explained. "If your child has these symptoms, if they have anxiety, get them tested. Get their genetic testing done and see what their bodies can tolerate."

"It's not your typical comeback story," Choate said. "It took me a while to see it could help people and it would be selfish not to share it."

Gerrit is now a junior at SMU, where he plays linebacker and special teams.

Prior to his junior season, Choate was promoted from walk-on to scholarship athlete at his father's alma mater.

"He's a warrior," Fifi said, wiping tears from her eyes. "He takes a beating and gets back up."

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