PITTSBURGH (KDKA) – Richard Vetstein got both doses of the Moderna COVID-19 vaccine.

“The second one was definitely much, much heavier, much stronger reaction,” he says. “I woke up at like 4 a.m., just pretty bad flu-like symptoms and stomachache and everything else.”

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That includes vivid dreams.

“One of them was, I saved a Belgian town from the Nazis, so that was interesting. The other one, I was on the Titanic,” he says, “You wake up, and you’re like, ‘what was that?'”

He posted his experience on social media and was surprised at the response.

“A bunch of people commented they also had weird dreams, too, after the vaccine,” he says.

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Sleep specialists are hearing stories like this from their patients.

“We’re seeing a lot of anecdotal reports,” says Dr. Dan Shade, a sleep specialist at the Allegheny Health Network. “The literature really doesn’t support this right now, but it’s early.”

After immunization, or with a COVID infection, or just during the pandemic in general, Dr. Shade says his patients have commented on bizarre dreams.

“Along with a lot of viral or serious illnesses, is that it really affects the sleep wake cycle,” he explains.

He doesn’t have a precise explanation, but guesses it has something to do with poor sleep from the anticipation of side effects.

“They’re expecting to experience fever, muscle pain, headache and they’re probably not sleeping well,” he says. “The most common reason we remember dreams is our sleep is disrupted.”

Whether the immune response is reacting with brain cells, it’s too soon to say.

“We’re going to look back on the data years from now, and you know what, these dreams weren’t just PTSD, there was actually a physiologic cause for it,” says Dr. Shade.

If a booster dose is needed in the future, the intense dreams won’t stop Richard. ”

Ventilator versus feeling a little bad, a bad dream. I’m sorry, but I’ll take that tradeoff,” he says.

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Severe illness with COVID would be the bigger nightmare.