‘The Big Bang Theory’: No One Is Sure If Sheldon Cooper Is Allergic To Cats, But Jim Parsons Sure Is

The Big Bang Theory was one of CBS’s most successful shows for 12 seasons. The series, however, is not without its critics. Those who oppose its greatness have pointed to serious plot holes as the show’s biggest misstep. Sheldon Cooper’s cat allergy, or lack thereof, is one of the most commonly cited plot holes from the show. While fans never found out for certain if Sheldon was allergic to cats, one thing is for sure, Jim Parsons, the actor who portrayed Sheldon, certainly is.

Sheldon protested Leonard’s interest in adopting a cat

In season 1, Leonard Hofstadter decided he wanted to adopt a cat, regardless of the roommate agreement he signed with Sheldon. The roommate agreement expressly prohibited either roommate from having a pet, apart from service animals. Sheldon protested Leonard’s interest in getting a cat, but Leonard insisted that he had taken Sheldon’s asthma into account.

Leonard Hofstadter and Sheldon Cooper in 'The Big Bang Theory'
Leonard Hofstadter and Sheldon Cooper in ‘The Big Bang Theory’ | Monty Brinton/CBS via Getty Images

The statement made fans assume that Sheldon was allergic to cats, or, at the very least, cat dander aggravated his pre-existing asthma. Several seasons later, it would seem that Sheldon had no issue having cats around. Not only did one cat not aggravate his asthma, but 25 didn’t seem to have any effect on him, either.

Sheldon later adopted multiple cats after his breakup

Sheldon wasn’t one for romance, but his relationship with Amy Farrah Fowler seemed to change all that. After one of the couple’s breakups, Sheldon refused to come to terms with his feelings. Instead of admitting he was a little heartbroken, he decided to adopt a friend. Instead of one cat, though, he adopted 25.

Jim Parsons as Sheldon Cooper
Jim Parsons as Sheldon Cooper | Sonja Flemming/CBS via Getty Images

Alarmed by Sheldon’s sudden interest in cats and the smell in the apartment, Leonard called Sheldon’s mother to deal with the issue. She eventually got Sheldon and Amy back together, and Sheldon agreed to give away his cats. No one ever mentioned Sheldon’s cat allergy again.

The Big Bang Theory star, Jim Parsons, is absolutely allergic to cats

While Sheldon’s feline allergy remains a mystery, there is one thing for certain; Parsons is allergic to cats. The The Big Bang Theory star recently sat down for an interview on The Ellen DeGeneres Show and shared that he, unlikely his character, is certain about his allergy. Parsons recalled that, at one point, he told producers on The Big Bang Theory that he was allergic to cats, shortly before they penned a script that found him surrounded by them.

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He told DeGeneres, “…they came up and asked me, ‘Are you allergic to cats by any chance?’ And I said, ‘Yeah I am, my eyes get puffy and whatever.’ About a week later, the script showed up with a box of Claritin, and it was like, ‘Here, we’re going to do one where you’re surrounded by cats the whole episode.” Parsons is currently producing another show that has him near a ton of feline friends. He is working on Call me Kat. The comedy starring former co-star, Mayim Bialik, focuses on a woman who runs a cat café.