Liev Schreiber Says Migraine Led to Temporary Amnesia While Onstage in Broadway's “Doubt: '”Worst Nightmare'

“The worst nightmare that an actor could possibly ever experience,” the 'Ray Donovan' star said

Liev Schreiber is opening up about the rare medical condition he suffered while starring in the Broadway production of Doubt: A Parable

During an appearance on Late Night with Seth Meyers, the 56-year-old actor revealed he had a health scare during the show, where he stars as a priest, Father Flynn.

“The worst nightmare that an actor could possibly ever experience,” the actor began. “I was in my dressing room and I had a terrible headache. I thought it was maybe a fast food headache, but it felt a little stronger than that. I’m walking down the stairs and I’m thinking, ‘This is not normal. I don’t feel okay.’ "

The Ray Donovan alum knew “something was really wrong” when he saw his costar Amy Ryan backstage and couldn’t remember her name. After trying to shake it off, he said things only got worse when he went out onstage and completely forgot his lines.

“It all vanishes. The play is gone from my head ... I know I’m in a play but I don’t know what play I’m in,” Schreiber explained.

Related: Jeff Probst Had Rare Temporary Amnesia That Left Him with 'Absolutely No Memory'

He continued, “My doctor, who’s a friend, shows up and he had a terrified expression. My wife shows up, she looks terrified. I think, ‘Okay, I’ve had a stroke. This is it.’ "

Schreiber said that he got an MRI and it showed that there was no brain bleed, and his brain looked “perfectly fine.” A neurologist then told the actor that he had a condition called transient global amnesia.

“Apparently it’s brought on by migraines and rigorous coitus,” he joked.

Transient global amnesia (TGA) is a rare medical condition where an individual experiences a sudden episode of memory loss and confusion, according to the Cleveland Clinic. Triggers of the condition include migraines, physical exertion, sexual intercourse, emotional or psychological stress and sudden immersion in cold or hot water.

TGA is most common in people of middle or older age, and it will resolve itself within 24 hours. There are no long-term effects of the condition.

<p>Lloyd Bishop/NBC via Getty</p> Liev Schreiber on <em>Late Night with Seth Meyers</em>

Lloyd Bishop/NBC via Getty

Liev Schreiber on Late Night with Seth Meyers

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"The guy said, ‘You’ll never have this again and it’ll be gone in 8 to 24 hours,’ which I didn’t believe,” Schreiber told Meyers. “You know, as a typical sort of Jewish hypochondriac person, I’m convinced that I had a stroke and they just didn’t find it.”

However, the doctor appeared to be right. “I go to sleep, I wake up, I remember the whole play,” he added. “I never had another problem with it. I was embarrassed and thought everyone would think I was lying and taking a night off from the theater.”

Meyers then teased that he’s “so sad” that the Emmy-nominated star got TGA from a migraine rather than from sex.

“I know!” Schreiber said with a laugh. “When the other option is to literally have your brains f***** out, I had to get it from a migraine.” 

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