The reality star and podcaster was taken into A+E by his fiancée Sophie Habboo after struggling to breathe and needed urgent attention.
She later shared the news on her Instagram Stories, telling fans: "Sorry for the MIA on Insta – had the most wonderful Christmas and I hope you all did as well.
"Jamie has been in hospital for steroids as it turns out he’s allergic to the new pup and his asthma has got out of control.
"So as you can imagine I’ve been quite stressed for them both,’ she added.
"Going to the doctor tomorrow so will keep you all updated. But sending everyone all my love to everyone."
Laing and Habboo, who both host podcast Nearlyweds, announced they had expanded their family with the puppy last week.
Laing – who was a finalist on Strictly in 2020 – shared photos cradling the adorable dog in a blanket and revealed his name was Bobbie.
"I’ve said no to a dog for a long time but finally had to give in to Sophie’s constant nagging," Laing joked in his Instagram post. "It’s peeing everywhere, pooping all over the place, she doesn’t know her name and ignores me, she sleeps all day and is awake during the night, wants to cuddle Sophie and not me but somehow I still find her pretty damn irresistible…
"Plus I get to choose her second name which probably was a big mistake, any ideas?"
The comment saw a slew of responses from their famous pals, with Made In Chelsea co-star Oliver Proudlock joking: "U know what comes next bro!"
The new puppy comes a year after they announced their engagement, where Laing surprised Habboo by decorating the restaurant they had their first date with roses and petals in order to pop the question.
She later shared the happy news on Instagram and said: "WE ARE GETTING MARRIED!!!!!!!!!!!! I cannot wait to spend the rest of my life with you."
"I couldn't think of anything better than spending the rest of my life with you @habboosophie.," Laing responded.
The couple have been together since 2019.
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