Don’t Mess with the Immune System (Say NO to Tylenol!)

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Just say NO to Tylenol

Tylenol may reduce the effectiveness of the vaccine.

What is the connection between Tylenol/Acetaminophen/Paracetamol with Autism?

What is the story with Reye’s syndrome?  When did rates of Autism begin to climb?  When did the rates of autism “stall?”

What is glutathione? Why is this important?

Research citations for Acetaminophen/Tylenol

Ji Y, Azuine RE, Zhang Y, Hou W, Hong X, Wang G, Riley A, Pearson C, Zuckerman B, Wang X. Association of Cord Plasma Biomarkers of In Utero Acetaminophen Exposure With Risk of Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder in Childhood. JAMA Psychiatry. 2020 Feb 1;77(2):180-189. doi: 10.1001/jamapsychiatry.2019.3259. PMID: 31664451; PMCID: PMC6822099.

Khan FY, Kabiraj G, Ahmed MA, Adam M, Mannuru SP, Ramesh V, Shahzad A, Chaduvula P, Khan S. A Systematic Review of the Link Between Autism Spectrum Disorder and Acetaminophen: A Mystery to Resolve. Cureus. 2022 Jul 18;14(7):e26995. doi: 10.7759/cureus.26995. PMID: 35989852; PMCID: PMC9385573.

Alemany S, Avella-García C, Liew Z, García-Esteban R, Inoue K, Cadman T, López-Vicente M, González L, Riaño Galán I, Andiarena A, Casas M, Margetaki K, Strandberg-Larsen K, Lawlor DA, El Marroun H, Tiemeier H, Iñiguez C, Tardón A, Santa-Marina L, Júlvez J, Porta D, Chatzi L, Sunyer J. Prenatal and postnatal exposure to acetaminophen in relation to autism spectrum and attention-deficit and hyperactivity symptoms in childhood: Meta-analysis in six European population-based cohorts. Eur J Epidemiol. 2021 Oct;36(10):993-1004. doi: 10.1007/s10654-021-00754-4. Epub 2021 May 28. PMID: 34046850; PMCID: PMC8542535. – “Results indicated that children prenatally exposed to acetaminophen were 19% and 21% more likely to subsequently have borderline or clinical autism spectrum condition (OR = 1.19, 95% CI 1.07-1.33) and ADHD symptoms (OR = 1.21, 95% CI 1.07-1.36) compared to non-exposed children.”

Patel E, Jones Iii JP 3rd, Bono-Lunn D, Kuchibhatla M, Palkar A, Cendejas Hernandez J, Sarafian JT, Lawton VG, Anderson LG, Konsoula Z, Reissner KJ, Parker W. The safety of pediatric use of paracetamol (acetaminophen): a narrative review of direct and indirect evidence. Minerva Pediatr (Torino). 2022 Dec;74(6):774-788. doi: 10.23736/S2724-5276.22.06932-4. Epub 2022 Jul 13. PMID: 35822581. “Based on this evidence, it can be concluded without any reasonable doubt that oxidative stress puts some babies and children at risk of paracetamol-induced neurodevelopmental injury, and that postnatal exposure to paracetamol in those susceptible babies and children is responsible for many if not most cases of ASD.”

Sil A, Ravi MD, Patnaik BN, et al. Effect of prophylactic or therapeutic administration of paracetamol on immune response to DTwP-HepB-Hib combination vaccine in Indian infants.Vaccine. 2017 Apr 24. pii: S0264-410X(17)30315-8.

This study shows that acetaminophen (paracetamol) does not affect seroresponse.

Schultz ST, Gould GG. Acetaminophen Use for Fever in Children Associated with Autism Spectrum Disorder. Autism-open access. 2016;6(2):170.

Liew Z, Ritz B, Virk J, Olsen J. Maternal use of acetaminophen during pregnancy and risk of autism spectrum disorders in childhood: A Danish national birth cohort study. Autism Res. 2016 Sep;9(9):951-8.

Use of acetaminophen in pregnancy was related to a specific type of ASD, but not all types.

Liew Z, Ritz B, Rebordosa C, Lee PC, Olsen J. Acetaminophen use during pregnancy, behavioral problems, and hyperkinetic disorders. JAMA Pediatr. 2014 Apr;168(4):313-20.

Acetaminophen use in pregnancy is more likely to cause ADHD and hyperkinetic disorders.

Schultz ST, Klonoff-Cohen HS, Wingard DL, Akshoomoff NA, Macera CA, Ji M. Acetaminophen (paracetamol) use, measles-mumps-rubella vaccination, and autistic disorder: the results of a parent survey.Autism. 2008 May;12(3):293-307.

“Acetaminophen use after measles-mumps-rubellavaccination was significantly associated with autistic disorder when considering children 5 years of age or less.”

Creagh O, Torres H, Rivera K, Morales-Franqui M, Altieri-Acevedo G, Warner D. Previous Exposure to Anesthesia and Autism Spectrum Disorder (ASD): A Puerto Rican Population-Based Sibling Cohort Study.Bol Asoc Med P R. 2015 Jul-Sep;107(3):29-37.

Wysocki J, Center KJ, Brzostek J, et al. A randomized study of fever prophylaxis and the immunogenicity of routine pediatric vaccinations. Vaccine. 2017 Apr 4;35(15):1926-1935.

Parker WHornik CDBilbo S, et al. The role of oxidative stress, inflammation and acetaminophen exposure from birth to early childhood in the induction of autism. J Int Med Res. 2017 Apr;45(2):407-438.

“Thus, one explanation for the increased prevalence of autism is that increased exposure to acetaminophen, exacerbated by inflammation and oxidative stress, is neurotoxic in babies and small children.

Tully JPetrinovic MM. Acetaminophen study yields new insights into neurobiological underpinnings of empathy. J Neurophysiol. 2017 May 1;117(5):1844-1846

Schultz STGould GG. Acetaminophen Use for Fever in Children Associated with Autism Spectrum Disorder. Autism Open Access. 2016 Apr;6(2). pii: 170. Epub 2016 Mar 28.

Lesson tags: autism, fever, tylenol
Back to: Vaccines Demystified


  • Avatar
    Shelby Flores
    April 3, 2023 at 7:48 pm

    Hi Erika, would you also recommend avoiding Tylenol while breastfeeding? I get terrible headaches at least once every month or two and Tylenol is always my go-to pain med, however, my son is exclusively breastfed and I worry how much crosses over into my breast milk. I only take it when I absolutely can’t bare the pain any longer and always the minimum dosage, but would love to hear any alternatives you recommend if you think it’s still not a good idea for a nursing mama to take. Thank you!

      • Avatar
        Shelby Flores
        April 4, 2023 at 3:16 pm

        Thank you for the information!

  • Avatar
    Joy Ross
    January 21, 2023 at 8:07 pm

    Hi Erika,

    You covered acetaminophen in this video, but didn’t touch on ibuprofen. Does ibuprofen carry the same/similar risks as acetaminophen? Is there any good literature on the topic? Thanks so much!

  • Avatar
    Tatiana Shuvarikova
    December 6, 2022 at 4:10 pm

    Hello Dr K.,

    Thank you very much for such a great information!

    My daughter was sick a couple of times before she was 1 year old, and she developed a very high fever around 104.5. I was really nervous and gave my daughter Tylenol a few times (although i felt like I should not have, my daughter seemed to be just fine). But with the pressure from the doctor who thinks that I should give Tylenol to my daughter every 4 hours when she has fever higher than 102, and with the lack of knowledge I gave in. When fever is pretty high do you still recommend not to give Tylenol?

  • Avatar
    April 10, 2018 at 9:28 pm

    Hi Dr. K, with my daughter’s 4 months shots she ended up with a fever that evening of about 102. If you are recommending not to use Tylenol to relieve a fever how do you provide relief post-shots to a baby that is uncomfortable with a rising fever?

    • Avatar
      Jaclyn Hagel
      January 13, 2021 at 11:29 pm

      Dr. K, are you able to comment on Ashley’s question above?

  • Avatar
    March 28, 2018 at 1:02 am

    Is there anything I can do to help increase glutathione production in my infant and other children? Also, if I am a homozygous carrier of the MTHFR mutation (C677T), are my kids definitely carriers of at least one mutation? Should I be extra concerned about vaccinations given they most likely have a reduced ability to detoxify because of this mutation? Are there any supplements I can give to help them detox the ingredients in vaccines that could be harmful?

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