Paracetamol Disrupts Early Embryogenesis by Cell Cycle Inhibition
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Paracetamol
Embryogenesis
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A study found that paracetamol disrupts early embryogenesis by inhibiting cell division, sparking discussions about its potential effects on reproductive health and the need for caution when using the medication.
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I wonder if it might also slow healing of wounds, or wherever else intense cell division happens.
I'm not sure if that was supposed to be sarcastic, but these two people have done more harm to public health, and are responsible for more health dis/mis-information, than pretty much anyone I can think of. (I am a biochemist, no conflict of interest)
As distinct from the retort that “absence of evidence is not evidence of absence”: It can be, if you’ve tried hard enough to gather the evidence and come up short—which is what these guys have done.
https://hsph.harvard.edu/news/using-acetaminophen-during-pre...
https://ehjournal.biomedcentral.com/articles/10.1186/s12940-...
https://health.clevelandclinic.org/pregnancy-safe-medication...
While they do list some medicines, note that they also say check with your doctor first.
Okay some don't, particularly North American and Northern/Western European ones.
But mostly, on average, physicians always try to prescribe you something.
Prostaglandins are an inflammatory hormone that do a variety of things, but specifically PGE2 plays a role in muscle stem cell activation to divide and produce more muscle fibers. The effect is probably realistically small, but you will leave gains on the table by taking ibuprofen after hard workouts.
Though the science is not completely established here and there are some exceptions (obvious ones like cancer, etc...)
> These results suggest that APAP should be used with caution by women attempting to conceive. Given that cell division is fundamental to all development, further investigation is now warranted to substantiate these findings and to elucidate possible implications for other developmental processes, such as gonadal and brain differentiation.
Both of my parents are/were heavy smokers drinkers from their teenage years. Mom died of lung cancer from smoking. Kind of wild to think that the odds were really stacked against my birth.
For instance, if spontaneous abortion is normally 1% and smoking increases it to 2%, then that’s a 100% increase. Now, I don’t know the actual numbers, and smoking is just generally not good for one’s health, but I wouldn’t go as far to say things were stacked against you.
"The meta-analysis showed a significant association between maternal tobacco smoking during pregnancy and increased risk of ADHD in offspring."
Mohammadian M, Khachatryan LG, Vadiyan FV, Maleki M, Fatahian F, et al. (2025) The association between maternal tobacco smoking during pregnancy and the risk of attention-deficit/hyperactivity disorder (ADHD) in offspring: A systematic review and meta-analysis. PLOS ONE 20(2): e0317112. https://doi.org/10.1371/journal.pone.0317112
"Compared with unexposed controls, individuals with PAE reported significantly higher frequencies of problems with hearing, dentition, heart, cancer, gastritis, kidney stones, bladder, diabetes, thyroid, skin, and seizures."
Coles, C.D., Shapiro, Z.R., Kable, J.A., Stoner, S.A., Ritfeld, G.J. & Grant, T.M. (2024) Prenatal alcohol exposure and health at midlife: Self-reported health outcomes in two cohorts. Alcohol: Clinical and Experimental Research, 48, 2045–2059. https://doi.org/10.1111/acer.15441
"Our results indicate that perinatal exposure to maternal smoking is associated with increased risks of CVD events, and such relations are modified by adulthood smoking behaviors."
H., Liang, Z., Wang, H., Cardoso, M. A., Heianza, Y., & Qi, L. (2021). Perinatal exposure to maternal smoking and adulthood smoking behaviors in predicting cardiovascular diseases: A prospective cohort study. Atherosclerosis, 328, 52–59. https://doi.org/10.1016/j.atherosclerosis.2021.05.009
"Our findings support previous findings suggesting the detrimental effects of prenatal binge drinking on child cognition. Prenatal alcohol exposure at levels less than daily drinking might be detrimentally associated with child behavior. The results of this review highlight the importance of abstaining from binge drinking during pregnancy and provide evidence that there is no known safe amount of alcohol to consume while pregnant."
Flak, A. L., Su, S., Bertrand, J., Denny, C. H., Kesmodel, U. S., & Cogswell, M. E. (2014). The association of mild, moderate, and binge prenatal alcohol exposure and child neuropsychological outcomes: a meta-analysis. Alcoholism, clinical and experimental research, 38(1), 214–226. https://doi.org/10.1111/acer.12214
You may not not want to hear this, but let's put it plainly: Prenatal smoking and alcohol is clear and obvious child maltreatment.
The implied causation annoys me. ADHD is hereditary, even if if the mother does not smoke. People with ADHD smoke ten times more often.
More broadly speaking, anything that is claimed to be "hereditary" (which for ADHD the scientific consensus is that it is not exclusively but estimated at around 70%) could also be early nuture and prenatal environment. The way genetic inheritance is researched (identical twins vs. fraternal twins) cannot account for this. [2]
[1] e.g.
"ADHD has been clearly linked with numerous environmental risk factors, particularly around the prenatal and perinatal period. Some of the most robust risk factors identified are maternal prenatal health conditions and psychological distress (e.g. hypertension, obesity, pre-eclampsia, immune activation), in utero exposure to poor diet (with critical factors still being determined), teratogenic effects of certain medications (e.g. acetaminophen) and environmental exposures (e.g. lead), as well as neonatal factors such as prematurity and low birth weight [27]. Other extreme exposures in the postnatal environment (such as extreme infant emotional neglect) have also been associated with an ADHD syndrome [28, 29]."
Cecil, C. A. M., & Nigg, J. T. (2022). Epigenetics and ADHD: Reflections on Current Knowledge, Research Priorities and Translational Potential. Molecular diagnosis & therapy, 26(6), 581–606. https://doi.org/10.1007/s40291-022-00609-y
"The convincing evidence for genes as risk factors for ADHD does not exclude the environment as a source of etiology. The fact that twin estimates of heritability are less than 100% asserts quite strongly that environmental factors must be involved. ADHD’s heritability is high, and that estimate encompasses gene by environment interaction. Thus, it is possible that such interactions will account for much of ADHD’s etiology. Environmental risk factors likely work through epigenetic mechanisms, which have barely been studied in ADHD [148]. The importance of the environment can also be seen in the fact that, as for other complex genetic disorders, much of ADHD’s heritability is explained by SNPs in regulatory regions rather than coding regions [149]."
Faraone, S. V., & Larsson, H. (2019). Genetics of attention deficit hyperactivity disorder. Molecular psychiatry, 24(4), 562–575. https://doi.org/10.1038/s41380-018-0070-0
"Parental stress and parental depression were significantly associated with increased risk for ADHD overall and both symptoms and diagnosis. Specifically, maternal stress and anxiety, maternal prenatal stress, maternal depression, maternal post-partum depression, and paternal depression were positively associated with ADHD. In addition, parental depression was associated with symptoms of ADHD inattentive and hyperactive/impulsive subtypes. Parental antisocial personality disorder was also positively associated with ADHD overall and specifically ADHD diagnosis. Prenatal antidepressant usage was associated with ADHD when measured dichotomously only. These findings raise the possibility that prevention strategies promoting parental mental health and addressing parental stress could have the potential for positive long-term impacts on child health, well-being, and behavioral outcomes."
Robinson, L. R., Bitsko, R. H., O'Masta, B., Holbrook, J. R., Ko, J., Barry, C. M., Maher, B., Cerles, A., Saadeh, K., MacMillan, L., Mahmooth, Z., Bloomfield, J., Rush, M., & Kaminski, J. W. (2024). A Systematic Review and Meta-analysis of Parental Depression, Antidepressant Usage, Antisocial Personality Disorder, and Stress and Anxiety as Risk Factors for Attention-Deficit/Hyperactivity Disorder (ADHD) in Children. Prevention science : the official journal of the Society for Prevention Research, 25(Suppl 2), 272–290. https://doi.org/10.1007/s11121-022-01383-3
[2]
"twin studies fail to separate the effects of genes and the prenatal environment. This failure casts doubt on claims of the relative effects of genes and environment on intelligence, psychiatric disorders, personality and other psychological variables, and other conditions."
https://www.psychologytoday.com/gb/blog/looking-in-the-cultu...
"Although many twin studies have been conducted (which is quite an understatement; there are almost 9,000 hits for “twin study” on PubMed!), there have long been critics who argue that they are scientifically worthless."
Smith, Jinkinson. (2020). The debate over twin studies: an overview. http://dx.doi.org/10.22541/au.159674847.78026661
"Because heritability is defined by both genetic and environmental influences, it is not a fixed characteristic of a disease or trait, but a population-specific estimate, analogous to, for example, the mean height, cholesterol level or life expectancy in a population. It also cannot be interpretated at the family or individual level."
Kaprio J. (2012). Twins and the mystery of missing heritability: the contribution of gene-environment interactions. Journal of internal medicine, 272(5), 440–448. https://doi.org/10.1111/j.1365-2796.2012.02587.x
More: https://en.wikipedia.org/wiki/Twin_study#Criticism
My mom's dead from lung cancer, and my dad is basically on palliative care. He's a barely walking billboard for "smoking is bad for you".
https://en.wikipedia.org/wiki/Paracetamol_poisoning
Since it’s a mild and really common painkiller, sometimes seen as not dangerous, someone uneducated about it who is really suffering could easily take 3 or 4 times the dose.
Unlike a lot of drugs, you are not going to have a lot of immediate side effects if you overdose on paracetamol. You’ll just horribly die some days after,
And the solution is simple: educate people about that.
And it's not something hard to do, just have pharmacists say “respect the dose as it will kill you if you don't” every time they sell things and it'll work.
It's funny that in a country where you can win massive sums of money on stupid trials a drug like paracetamol is sold without supervision.
She would take a dose for a headache, ten minutes later she'd forgotten so she'd take another dose, ten minutes later, she had forgotten, take another dose, rinse and repeat until it's time for a trip to the hospital.
Maybe it wasn't ten minutes between, probably fewer given how much she'd ended up taking. This happened thirty or so years ago.
Other drugs like theophylline have ceased to be prescribed for a similar reason alternatives were available, but due to drug marketing, acetaminophen is touted as the "safe" pain reliever.
Paracetamol's patents have expired long ago and there's not much profit to be made out of it (nowadays it's mostly not being made in the West, but imported from China, unlike profitable medicine).
The reason why it's still used it's that it's much better than the alternatives, despite the risks (it's only risky if you don't respect the doses by the way).
Roughly:
- Paracetamol overdose can cause severe liver damage and may be fatal.
- Ibuprofen in high doses can lead to kidney injury and stomach bleeding.
- Aspirin overdose may result in salicylate poisoning, causing ringing in the ears, confusion, and metabolic acidosis.
There is a rich and varied multidimensional field of danger, from aspects like the safety-margin between regular/dangerous dose levels, the chronology of how it can spike or accumulate, whether there's feedback in advance of damage, etc.
Yeah, I can poison myself drinking clean water, but it's hard.
Together they have higher pain killung effects than each alone, and the side effects are reduced as they affect different body parts. And the vitamin C reduces the damage to the stomach lining.
Meanwhile, taking ibuprofen can negate the effect aspirin has when taken against cardiovascular diseases. Not a huge problem if you're just taking it as a painkiller, but not everyone can combine the two. That's another potential reason to take paracetamol over some NSAIDs, though you should obviously consult a doctor if you're taking prescription medicine of any kind.
That is wild.
If true, it would have to be genetic? I mean, unless it is chronic dehydration from their sense of humor?
Oxygen toxicity is not a risk for most people. You either are a scuba diver regularly working at depths beyond what most do or are taking supplemental oxygen while under the care of a doctor. You are not at risk of oxygen toxicity reaching into your bathroom medicine cabinet.
Total culture shock for me, as in Europe the default for children is rectal ingestion (which is probably a culture shock as well for Americans). Any how, with pills it is much easier to avoid overdose.
We had blood test done (on the doctor's recommendation), and luckily there is no sign of any damage, but prescription errors do happen (even if they are rare) and it's much easier with liquids (you probably wouldn't give 8 pills to a baby, but 8ml doesn't seem so bad).
There's no “as in Europe”, every European country is different. In France the default is also liquid form, but the pipette is graduated is kilograms of baby weight, which limit the errors you can make (you know your kid doesn't weight 15kg when his weight is around 8).
I think the mistakes also come when the child spits out part of the liquid, and parents give another dose.
Otherwise, it's much easier to get them to take a pill than drink a liquid.
Never met a non autistic child who would spit or drool out calpol. I'd take the stuff myself as an adult it tastes brilliant.
> Total culture shock for me, as in Europe the default for children is rectal ingestion (which is probably a culture shock as well for Americans)
Huh are you talking about new born babies or something? I've been to a few different EU countries and you can buy liquid stuff for kids in the chemists. (Spain, france, germany, italy) source me as a child getting the stuff when I was sick abroad and the local doc sold my parents basically some off brand calpol.
We ended up crushing and diluting tablets in milk, which he would drink (you waste a lot of milk to hit the right factor).
Results: "Suicidal deaths from paracetamol and salicylates were reduced by 22% (95% confidence interval 11% to 32%) in the year after the change in legislation on 16 September 1998, and this reduction persisted in the next two years. Liver unit admissions and liver transplants for paracetamol induced hepatotoxicity were reduced by around 30% in the four years after the legislation. Numbers of paracetamol and salicylate tablets in non-fatal overdoses were reduced in the three years after the legislation. Large overdoses were reduced by 20% (9% to 29%) for paracetamol and by 39% (14% to 57%) for salicylates in the second and third years after the legislation. Ibuprofen overdoses increased after the legislation, but with little or no effect on deaths."[1]
[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC526120/
So if you're going to off yourself you'd have to stock pile or roam around shops picking up.
There is a not insignificant number of suicides where people just say fck it I'll just kill myself but they don't want to go out to any real bother to do it i.e. they don't pre-plan it it's just spur of the moment. A bottle of kill yo self pills is pretty easy. Cupboard, swallow, drink down some water, die. But having to go out and buy a bunch over a few days or like drive around in your car just buying as many as you can. Like you'd have to look it up to check you're going to buy enough.
Back when that law came in when they didn't reduce the total amount you could buy at one time so if you went in and bought like 10 packs at the supermarket then the person at the till would be like ok this person's going to kill themselves so again that would require a bit of balls from the would be kill yo selfer.
I think you can buy a bottle of like 100 x 500mg for like $20 in the USA. That's like over 2 weeks swigging at the max amount. Like you don't need that many, 3-4 days is enough shouldn't be taking that much of the stuff.
- different packages of the same medication have different doses per pill. So you might read one package that says to take two pills, then later you buy a different package of the same painkiller that says one pill, but you're lazy, and don't read the label for this, and assume it is the same as last time, so you end up doubling the dose.
- For ibuprofen, the label often says if one dose isn't sufficient, then you can take another pill (with a maximum number in 24 hours). People may assume this is the case for Tylenol as well, but I don't think it is.
- people may read the size of the dose, but skip over the warning about the maximum you can take in a 24 hour period.
- The directions are in small hard to read text, which makes all of the above points worse.
Not that any of those are a good excuse not to read the label, but, well, people make bad decisions all the time.
This is why Ibuprofen is perhaps the better default painkiller.
I guess the safest way is to take up the treatment in a hospital, to check for immediate bad reactions.
On the other hand, like with many medications, severe allergies and individual sensibilities causing side effects often don't show up often in the short term, but rather suddenly after many dose intakes.
So I'm back where I started. Not disagreeing with what you say. It seems like these non-steroidal pain relief medications are poorly understood regarding their interaction with the whole body though.
Many OTC medications and even some prescribed ones (especially psychiatric medications) suffer from a very poor understanding and apparent lack of effort in improving the understanding of their mechanisms of action.
Not addictive, not hepatotoxic, not nephrotoxic.
Seems the reason for the ban / harder regulation in some countries is about the disturbance of blood-forming in some individuals (which can also be deadly, but I have no idea of the quantified risk here).
Ibuprofen and acetaminophen are more common for short-term treatment, at least that's what I've been taught.
Avoid taking them on a schedule, take them as needed and at the lowest effective dosage.
A.s.s. (lol) too, apart from the low-dose usage that some claim to be helpful with heart/artery diseases.
But from what I understand acetaminophen also dulls emotional pain like from being fired or breaking up with a girlfriend which is interesting.
I still prefer to take neither if I can avoid it and I'll hurt a little bit instead. Hurt a lot and I'd probably change my mind though.
Acetaminophen is not ibuprofen. But I also don't like planes because a friend of mine died in a car crash.
There is also the final sentence about preferring to take "neither". Which of course indicates _two_ substances.
But just to be safe, I don't think the liver and the kidneys are the same organ either :)
Ibuprofen is forbidden for pregnant women in the last 4 months in France at least - and by "forbidden", I mean "strongly advised against in a case of self medication".
That doesn't make it very safe, but NSAIDs carry well known risks during later stages of pregnancy, and opiods aren't exactly harmless either. Even aspirin carries risk (and aspirin doesn't even work as well compared to other drugs).
As far as I can tell paracetamol is still the first choice for painkillers while pregnant, but only because none of them are completely safe to use. It's probably fine for short term usage, but that also goes for non-pregnant people to be honest.
Some links:
https://hsph.harvard.edu/news/using-acetaminophen-during-pre...
https://jennifermargulis.substack.com/p/why-this-doctor-is-c...
Question: Does acetaminophen use during pregnancy increase children’s risk of neurodevelopmental disorders?
Findings: In this population-based study, models without sibling controls identified marginally increased risks of autism and attention-deficit/hyperactivity disorder (ADHD) associated with acetaminophen use during pregnancy. However, analyses of matched full sibling pairs found no evidence of increased risk of autism (hazard ratio, 0.98), ADHD (hazard ratio, 0.98), or intellectual disability (hazard ratio, 1.01) associated with acetaminophen use.
Meaning: Acetaminophen use during pregnancy was not associated with children’s risk of autism, ADHD, or intellectual disability in sibling control analyses. This suggests that associations observed in other models may have been attributable to confounding.
"We identified 46 studies for inclusion in our analysis. Of these, 27 studies reported positive associations (significant links to NDDs), 9 showed null associations (no significant link), and 4 indicated negative associations (protective effects). Higher-quality studies were more likely to show positive associations."
Autistic moms are more likely to have chronic illness, sensory issues, auto immune issues, etc thus are more likely to be taking medications. In the end, the autistic mom just passes her autistic genes to the baby.
I tested positive with COVID-19 on Tuesday and had a pretty high fever (103) with a terrible headache, but I didn't take ibuprofen. First, because it could lower my fever, second, because its anti-inflammatory effect would compromise my immune system response to the pathogen. Most people I know immediately try to lower their fever to reduce their discomfort and would immediately take it for headaches, too.
Not always. Blaming “lazy” and irresponsible parents is disgusting.
No it's not, in many case there's just no way the parent can tell something is about to go wrong.
> Something that has just a 2% incidence should not dictate 98% of the treatments.
This isn't the same argument, and I would agree if it was true, but you're distorting numbers as the actual prevalence estimations lie between 2 and 14%[1].
Now you could make the argument that 10% is low enough of incidence it shouldn't dictate the treatment of the other 90%, but that's not what you're doing, instead you are blaming helpless parents and cherry picking numbers, making nothing but noise.
Oh, and by the way, most parents aren't in fact giving their kids paracetamol for that particular reason (as most parents are simply unaware of the existence of febrile seizures), but to help their children sleep and rest (and so themselves can sleep). And in fact, resting being key in innate immunity efficiency, I'm not particularly convinced about the effectiveness of letting your kids cry all night because of the pain and fever. You do what you want with your own kids, but there's no justification for insulting other parents.
Good day.
[1]: https://www.bmj.com/content/351/bmj.h4240
Key Takeaways
- No Lasting Damage: Simple febrile seizures do not cause long-term brain damage, intellectual impairment, or learning disabilities.
- Benign Nature: Despite how terrifying they are to witness, febrile seizures are considered benign events in the vast majority of cases.
- Focus on Reassurance: The primary goal for healthcare providers is to reassure parents and caregivers, providing them with the knowledge and tools to manage a fever and understand the low risk of lasting effects.
How surprising given the rest of the conversation …
Please stop believing your sample of 3 kids is representative of the entire population. You were lucky to have kids who sleep well and that's good for you, but that doesn't make other parents lazy or irresponsible.
> I'm tired of parents who overprotect their children
You know what's even more tiring? Parents who judge other parents while not knowing anything about kids in general just because they happened to be lucky on one particular topic. You won't be lucky all the time though.
> to forcing them to wear helmets
I hope you won't regret saying that ever in your life, but being anti-helmet really is as idiotic as being an antivaxxer.
[0]: https://www.imdb.com/title/tt0085204
Helmets and bike gear are in industry and American industries have powerful lobbies.
This is BS, any kid could have had one and you simply wouldn't have known it, especially as a kid. Even if some kid died, your parents would likely have been aware of that, but kids around likely wouldn't have, unless they were in the same class or otherwise knew the victim personally. (Simple exercise, check how many child around you do you remember dying when you were a kid, and then check the mortality rate in your country for this age class. You'll realize that statistically during the time you were at school, a bunch of kids in your neighborhood actually died of random causes and you never knew about that).
> In fact, the first COVID-19 booster by Pfizer was only tested on mice, not on a single person even, yet it was administered to billions of people.
Again, this is complete nonsense. There were indeed a few rounds of human trial before mainstream use … That's infowars-level of antivax BS.
> Helmets and bike gear are in industry and American industries have powerful lobbies.
Of course, what's an online discussion without the mandatory conspiracy theory … I appreciate the originality though, as the “big helmet” lobby isn't something I had encountered before. I see you prefer tinfoil hats to bike helmets …
[0]: https://c19early.org/ib
They also do it with their kids because they want to help them. Also, some people have a lot on their plate, calling them lazy is not right thing to do. I have health insurance that covers me when my kids are sick (not in the US), so I can take care of them "properly ". This doesn't make me more responsible and someone else that works two jobs and can't afford to have sick kids lazy.
Also, I don't lower fever, even with my kids unless it prevents them from sleeping. But overstated is relative, it's happened to the kid next door from me. You don't want to be careless with infants.
I've been taking multiple paracetamol tablets for years now, almost out of habit now.
Anyway, I understand arguments for avoiding drugs, medicines and chemicals altogether. Clearly, everything is more complex than it seems and side effects can never be fully known or understood; especially on a case-by-base basis given that everyone's DNA is different and responds differently to chemicals. I only take Paracetamol if I have a migraine with visual aura which is quite rare. I don't take it for standard headaches.
Side note, here's a Scrubs clip from 2001 that shows just how ubiquitous Tylenol was.
https://www.youtube.com/watch?v=EcDWj7kZcRc
I know the anti-vax crowd is full of homeopaths, chiropractors, and tarot readers. But they're not wrong about one thing: drug companies make money by selling drugs. If we can't guarantee real oversight before those drugs hit the market, we're in deep trouble.
By the same logic it would now be effective against cancer, no?
it also messes with bone formation so be careful using it for any length of time
especially after athletic activity
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