By Rachael Robertson

Actress and longtime anti-vaccine activist Jenny McCarthy took to social media to weigh in on recent debates about acetaminophen (Tylenol), vaccines, and autism, sharing her concerns about glutathione depletion.

While some of McCarthy's claims are rooted in truth, an expert said that McCarthy mischaracterized the relationship between acetaminophen and glutathione and manipulated information to fit an agenda.

McCarthy, who describes herself as "pro-safe vaccine," said in an Instagram video to her millions of followers that "Tylenol basically depletes your glutathione," which she described as "your body's natural antioxidant ... that helps us detox all the environmental toxins that we're assaulted with every single day."

She went on to say that if someone were to go to their doctor and raise worries about aluminum in vaccines, a doctor may tell you that your body naturally excretes it.

"But what if your body is low in glutathione?" McCarthy posited. "What if that detox methylation system gets kind of jolted, broken, if you will, lowers so that it cannot detox the adjuvants, the aluminum in the body? Then it winds up floating around the body, attaching to brain, gut -- you name it." McCarthy recommended not taking Tylenol before or after vaccines and to get glutathione levels checked.

"I personally have never ordered a glutathione level or checked it in my entire life as a toxicologist," said Lauren Shawn, MD, an emergency medicine physician and medical toxicologist at Phelps Hospital in Sleepy Hollow, New York. "Glutathione level itself is not really clinically relevant to me in my practice."

As for vaccines, Shawn said that the recommendation to not take acetaminophen or other anti-inflammatories before a shot is to avoid blunting the immune response and has nothing to do with glutathione or fears of toxicity. Taking acetaminophen afterwards to manage symptoms is absolutely fine, she noted.

Glutathione is a tripeptide made up of three amino acids -- cysteine, glutamic acid, and glycine -- and is involved in the metabolism of medications, including acetaminophen, Shawn explained. Most of the drug will bind to glutathione, become inactive, and be excreted in urine. A small amount can be taken up by another liver enzyme and form the toxic metabolite N-acetyl-p-benzoquinone imine, which the body can detoxify if the patient is taking acetaminophen as prescribed.

"If you're taking Tylenol at recommended doses and not chronically exceeding the maximum, you are not depleting your glutathione," Shawn said.

Toxicity from acute or chronic overuse of acetaminophen is an actual concern, and N-acetylcysteine, which helps the body make glutathione, is the antidote.

Most healthy people consume the building blocks of glutathione in their diet, though some elderly people and those with renal disease, malnourishment or eating disorders, or genetic predispositions may have lower glutathione and thus higher risk for acetaminophen toxicity.

In the video, McCarthy shared that she and her son, who has autism, both have naturally low glutathione levels, even though she didn't take acetaminophen before or after vaccines, and they both get weekly glutathione IV infusions.

Shawn said glutathione is one of the hot new treatments in alternative medicine, even though evidence doesn't support the therapy.

"Best-case scenario you're giving yourself expensive urine," she added.

She also said anti-vaxxers like McCarthy and HHS Secretary Robert F. Kennedy Jr. "use the big medical terms and words, and they sort of touch on things that are kind of correct," but don't have the expertise to analyze and understand the data.

"I just think it's so dangerous that these celebrities and non-healthcare professionals are saying things as the truth without real evidence or understanding of what they're saying, and they're convincing other people to follow their lead," Shawn said.

This is different than informal patient networks in which people share information about managing their conditions, she pointed out, noting that people like McCarthy and Kennedy often push for a particular narrative, exaggerate risk, and blur the line between expertise and opinion.