Daniel Chong, a 24-year-old UC San Diego engineering senior, said he was picked up in a Drug Enforcement Administration raid near campus, locked in a 5-by-10-foot windowless federal cell and then forgotten, the U-T San Diego reported Wednesday.
Chong said he could hear agents chatting on the other side of the heavy cell door but screaming and kicking failed to draw their attention.
At one point, Chong said the lights went out and stayed off for several days.
He said he remembers biting his eyeglasses and using the broken shards to scrawl a note to his mother on his left arm.
In utter confusion, Chong said he ate some of the broken glass.
He said was forced to recycle his own urine to survive.
"It's impossible to describe hallucinations like these," he said. "I was completely insane."
When agents finally discovered Chong on April 25, he was badly dehydrated and likely just hours from death.
Paramedics rushed him to a nearby hospital where he spent five days recovering from a perforated lung that was the result of eating broken glass.
Chong's attorney said a lawsuit would be filed against the federal government.
He was not charged with any crime.
In a statement Monday, the DEA said it is investigating what happened.