Doctors say nightmares on Tamiflu are 'very common' — here's what you need to know

With more than 6 million people sick with the flu, according to CDC data, we’re officially in the thick of flu season. And, with that, doctors are regularly prescribing Tamiflu to patients to try to speed up recovery and lower the odds that people will have serious complications from the illness. But there’s one thing people should be aware of before they take the drug: It can cause hallucinations and nightmares.

In early January 2018, a 6-year-old in Florida began hallucinating after taking the drug and attempted to jump from a second-story window. Weeks later, another young girl in Florida suffered from hallucinations and seizure-like symptoms. “To see her have no light behind her eyes, no recollection, no nothing, was just — I’ve never been panicked like that in my life,” her mother, Winnie Duffy, told NBC 2. The internet is also filled with stories of kids having nightmares while on Tamiflu.

“I see it all the time. It’s very common — nightmares especially,” Gina Posner, MD, a pediatrician at Memorial Care Orange Coast Medical Center in Fountain Valley, Calif., tells Yahoo Lifestyle.

Tamiflu (generic name: oseltamivir phosphate) works in a very specific way. “In order for the influenza virus to spread and cause disease, it must replicate in our cells and then leave the cells to infect other cells,” Jamie Alan, PhD, an assistant professor of pharmacology and toxicology at Michigan State University, tells Yahoo Lifestyle. “Tamiflu works by not allowing the influenza virus to bud off the cell and leave the cell to infect other cells.”

While hallucinations and nightmares are known side effects, experts don’t know exactly why this happens. “Theoretically, Tamiflu cannot easily get into the brain,” Alan says. “However, we know that Tamiflu enters the brain because we do see these kinds of side effects in patients.” One theory is that if the brain’s protection, the blood-brain barrier, is compromised by inflammation from an infection like the flu, then the drug can cross into the brain, she says. Mouse studies have shown that Tamiflu can get into the brain if the blood-brain barrier is compromised, Alan points out.

This isn’t just something that happens with kids — adults “can and do” experience it too, but it’s often on a less extreme level, Alan says. “In mice, we can detect higher levels of Tamiflu in younger mice compared to older adult mice,” she explains. “One hypothesis is that the blood-brain barrier might be less developed in children; therefore, more Tamiflu can cross into the brain in younger patients.”

Unfortunately, there’s only so much you can do about this, other than provide extra TLC to your child. “If the symptoms are super-severe, I tell parents to stop giving their children the Tamiflu,” Posner says. Another option Alan suggests: You can ask your doctor about Xofluza, a newer drug that works against influenza that isn’t reported to have these side effects.

Read more from Yahoo Lifestyle:

• A man consumed an entire bottle of ED medicine — and the result might surprise you

• This little girl died within 48 hours of showing flu symptoms — doctors explain why

• There are 2 types of flu shots to choose from: Which one should you get?

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