Donald Trump has disclosed an unprecedented shift in the medical guidelines provided to Americans during a press conference regarding potential autism causes.

The president stated that the FDA will start informing physicians to advise pregnant women to refrain from taking acetaminophen, widely recognized by the brand name Tylenol, ‘unless it is medically necessary,’ such as in instances of ‘extremely high fever’.

He emphasized that pregnant women ‘have a responsibility’ to endure discomfort rather than consume Tylenol, only taking it if they ‘cannot bear it’ or are dealing with an extremely high fever.

‘Fight like hell not to take it,’ he said, also urging parents not to give it to children.  

While speaking at a press conference with Robert F Kennedy Jr, Trump also denounced America’s ‘disgraceful’ vaccine schedule, despite the connection between autism and vaccines having been debunked long ago.

This announcement was made as the administration revealed findings from a federal review led by the health secretary, who earlier this year claimed ‘autism devastates families’.

Trump described the increase in autism rates in the US as ‘one of the most alarming medical crises in history,’ referring to a 400 percent rise over the past several decades.

He said: ‘You know it’s something artificial. 

‘With Tylenol, don’t take it. There’s not an alternative to that.’ 

It’s thought that the active ingredient in Tylenol, known around the world as paracetamol, may hinder fetal brain development, but research has largely been inconsistent, and major health bodies still recommend it for pregnant women.

The maker of the Tylenol earlier pushed back against the Trump administration’s claims that the painkiller causes autism, branding it ‘dangerous’ and insisting its drug remains the safest option for pain and fever relief in pregnant women. 

Additionally, Trump praised the CDC’s latest move to stop recommending the combined MMR and varicella vaccine and urged Americans to break up the MMR vaccine into three separate shots because mixing them ‘could be a problem’. 

‘I’ve heard bad things about [the MMR] personally,’ Trump said, despite also calling himself a ‘big believer in vaccines’.  

On the flip side, Robert F Kennedy touted an ‘exciting’ development in autism improvement: the $2.50-per-pill drug leucovorin, which is derived from folic acid.

While research on leucovorin is also mixed, doctors specializing in the relationship between the drug and autism told the Daily Mail the administration’s focus on it ‘gives hopes’ to families across the country. 

Folic acid, also known as vitamin B9, is a vital nutrient that helps synthesize DNA and replicates and repairs cells throughout the body. 

Women are already advised to take folic acid during pregnancy to prevent birth defects in the fetal brain and spinal cord, but a growing body of research suggests it could help repair pathways in a child’s brain well after birth.

Dr Marty Makary, FDA commissioner, also said the agency plans to approve the use of leucovorin for autistic children, and it is expected to be covered by government-subsidized insurance, with Dr Mehmet Oz stating private insurance companies are ‘likely to follow.’ 

Trump said: ‘It’s not that everything is 100 percent understood or known, but I think we’ve made a lot of strides.

‘We understood a lot more than a lot of people who studied it, we think.

‘This is a very important day.’ 

Trump also repeated a long touted myth that there is no autism in the Amish community, which has been disproven.

The announcement comes as the Trump administration and Kennedy have made it a top priority to tackle America’s rising autism rates, with one in 31 children now estimated to have the condition compared to one in 150 children in 2000. 

Trump cited that the rate was closer to one in 20,000 decades ago but did not specify. Historical data suggests the president was exaggerating.  

Experts say the increase is largely due to a loosening of the definition of autism and because doctors have become better at detecting the condition. 

But others, including RFK Jr, have suggested toxins in the environment, older parents or maternal obesity could be behind the rise.

Kennedy said: ‘We are continuing to investigate multiplicity of potential causes.

‘We will be uncompromising and relentless in our pursuit. Whatever the answer is, we will tell you what we find.’ 

NIH head Dr Jay Bhattacharya also announced his agency would devote an additional $50million to studying the causes of autism.

He said: ‘The sharp rise of autism deserves an urgent response by the scientific community.’  

Acetaminophen is widely used by pregnant women, with about 60 percent taking the drug, to reduce fevers and pain that could harm both mother and baby.

Acetaminophen is found in Tylenol and a number of other medications, including over-the-counter cold and flu drugs such as DayQuil and NyQuil and sleep aids such as Excedrin PM.

Dr Makary said: ‘We now have evidence we cannot ignore.’ 

The drug is considered to be among the only safe and doctor-approved pain and fever reliever for use in pregnant women. 

Major medical organizations, including the American College of Obstetricians and Gynecologists, say it is safe for pregnant women to take the drug, although they recommend consulting with a doctor. 

ACOG said in a statement: ‘Today’s announcement by HHS is not backed by the full body of scientific evidence and dangerously simplifies the many and complex causes of neurologic challenges in children. It is highly unsettling that our federal health agencies are willing to make an announcement that will affect the health and well-being of millions of people without the backing of reliable data.

‘In more than two decades of research on the use of acetaminophen in pregnancy, not a single reputable study has successfully concluded that the use of acetaminophen in any trimester of pregnancy causes neurodevelopmental disorders in children.’

Dr Monique Botha, a developmental psychologist at Durham University in the UK, said in a statement released by the Science Media Center: ‘There is no robust evidence or convincing studies to suggest there is any causal relationship and any conclusions being drawn to the contrary are often motivated, under-evidenced, and unsupported by the most robust methods to answering this question.

‘I am exceptionally confident in saying that no relationship exists.’

Dr Randa Jaafar, a pain management specialist in New York City, told the Daily Mail: ‘There are many other factors of maternal use that have higher links with autism like smoking and alcohol use during pregnancy.

‘[Acetaminophen] can accumulate in the fetal liver and brain – that is what can affect brain development but it has to be taken in high amounts for this to happen by the mother, which would be rare unless a mom is overdosing on Tylenol.’ 

A spokesperson for Kenvue, which produces Tylenol and other popular drugs like Zyrtec and Benadryl, told the Daily Mail in a statement: ‘We believe independent, sound science clearly shows that taking acetaminophen does not cause autism. We strongly disagree with any suggestion otherwise and are deeply concerned with the health risk this poses for expecting mothers.

‘Acetaminophen is the safest pain reliever option for pregnant women as needed throughout their entire pregnancy. Without it, women face dangerous choices: suffer through conditions like fever that are potentially harmful to both mom and baby or use riskier alternatives.

‘The facts are that over a decade of rigorous research, endorsed by leading medical professionals and global health regulators, confirms there is no credible evidence linking acetaminophen to autism.

‘We stand with the many public health and medical professionals who have reviewed this science and agree. We will continue to explore all options to protect the health interests of American women and children.’

Folic acid-derived leucovorin, meanwhile, has seen an increasing body of evidence supporting its effectiveness.  

Folic acid’s naturally occurring form, folate, is found in foods such as leafy green vegetables, beans, and lentils. But research shows up to three in four autistic children don’t get enough folate supply to their brain, causing delays in speech and behavioral issues.

Dr Richard Frye, a pediatric neurologist at Rossignol Medical Center in Arizona, told the Daily Mail: ‘We find that up to 75 percent of children with autism have a blockage in the ability to get folate into the central nervous system. Folate levels in the central nervous system are restored with leucovorin at prescription doses.’ 

It’s believed these children have autoantibodies in their blood – a type of antibody that mistakenly targets and attacks the body’s tissues and organs.

These autoantibodies are known to block a protein called folate receptor alpha, a protein that transports folic acid from the blood into the brain and placenta.

Leucovorin is approved in the US for patients to protect their cells – especially blood cells – against the damaging effects of chemotherapy, but doctors can prescribe it ‘off label’ for other conditions since it has been deemed safe by the FDA.

Dr Frye, who has been studying leucovorin for the past 20 years and is one of just 50 doctors nationwide prescribing it to autistic children, estimates the drug helps about 70 percent of the children who take it. 

Dr Frye told the Daily Mail: ‘This is a safe, well-tolerated treatment which can improve lives of many individuals with autism. It is not a cure, but it improves the function of many children substantially.’ 

‘I think this is a major step forward to get many children with autism treated and improve their ability to function. 

‘It is particularly groundbreaking in the fact that many do not think autism can be treated at its core. This treatment fixes core biological deficits and therefore could be disease modifying. 

‘Recognition by the administration that there is such a treatment gives hope to many families.’

Speaking previously to the Daily Mail, parents working with Dr Frye revealed the ‘dramatic’ difference leucovorin made in their autistic children. 

The family of eight-year-old Ryan Baldridge Jr, for example, said their son went from ‘basically non-verbal’ to speaking full sentences within six weeks.

He even was finally able to tell his father that he loved him. 

And Nathaniel Schumann, 12, went from only being able to say one or two words at a time to finally being able to tell his family about what was bothering him. 

His mother told this website: ‘It is a combination of therapies as well as leucovorin, but when leucovorin was added to the mix, that’s when we noticed the change.’