• Rob Orman

34. Tylenol, Sleep, and Antibody Response. COVID vaccine side effects.

The COVID vaccines are upon us! In this episode we disambiguate COVID vax side effects and the historical effects of acetaminophen and sleep on vaccine antibody response.

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We Discuss:

Listener questions [0:00:30]

  • Does Rob still do ERcast? Yes.

  • How an mRNA vaccine works.

COVID mutations in Europe may increase transmissibility [00:04:40];

Recently published side effects and adverse reactions of Pfizer COVID vaccine [00:06:05];

  • Most (around 80%) had pain at the injection site. Not much difference between first and second injections

  • Pain slightly less common in those over 55

  • Fatigue was by far the most common systemic side effect -- occurring in over half of vaccine recipients (but almost a quarter of placebo patients).

  • Fever (temperature, ≥38°C) was uncommon after the first dose. After the second dose it happened in 16% of younger recipients and by 11% of older recipients.

  • High fever (temperature, 38.9 to 40°C) was rare -- it happened to 0.2% of vaccine recipients and 0.1% of placebo recipients reported fever after the first dose, as compared with 0.8% and 0.1%, respectively, after the second dose.

  • Fever and chills most predominant first 1 to 2 days after vaccination and then tapered off quickly after that

  • Muscle pain, chills, joint pain did happen after the first shot, around 10ish percent of the time and doubled in frequency after the second shot.

  • There were deaths in both the vaccine and placebo groups. Per the authors: “Two BNT162b2 recipients died (one from arteriosclerosis, one from cardiac arrest), as did four placebo recipients (two from unknown causes, one from hemorrhagic stroke, and one from myocardial infarction).“

Impact of acetaminophen and ibuprofen on vaccine antibody response [00:10:13];

  • In a 2009 study, infants given prophylactic acetaminophen with vaccination series had significantly lower antibody concentrations for multiple vaccine types.

  • Other studies have shown decreased antibody concentrations with acetaminophen as well as ibuprofen.

  • The biggest impact on immune response to vaccines seems to be if the medication is given at the time of vaccination. If it's taken therapeutically afterwards, the impact diminishes or disappears.

  • Some studies show no impact on antibody levels.

  • Has yet to be studied in COVID vaccines.

How sleep impacts vaccine antibody response [00:16:19];

  • The literature on this is a mixed bag, but I think there is enough signal that we should pay attention - as in get your vaccination around a time of quality sleep. The data:

  • Compared to good sleepers, college students with insomnia had a trend toward weaker antibody development after flu shots.

  • One month after getting hepatitis A vaccination, those allowed to sleep had double the antibody production compared to a group that stayed up all night. That was just a single night of sleep deprivation.

  • Sleep deprived men (but not women) had lower 5 day antibody response after flu vaccine. At 7 weeks there was no apparent effect of sleep deprivation.

  • Shorter sleep duration predicted decreased antibody response to hepatitis B vaccination.

  • Bottom line: We know sleep matters in myriad aspects of health. Adding to that, consider timing vaccinations for a time when you’ll have decent pre and post sleep.

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  • Saleh, Ezzeldin, M. Anthony Moody, and Emmanuel B. Walter. "Effect of antipyretic analgesics on immune responses to vaccination." Human vaccines & immunotherapeutics 12.9 (2016): 2391-2402. Full Text Full Text PDF

  • Prymula, Roman, et al. "Effect of prophylactic paracetamol administration at time of vaccination on febrile reactions and antibody responses in children: two open-label, randomised controlled trials." The Lancet 374.9698 (2009): 1339-1350.

  • Taylor, Daniel J., et al. "Is insomnia a risk factor for decreased influenza vaccine response?." Behavioral sleep medicine 15.4 (2017): 270-287.

  • Lange, Tanja, et al. "Sleep enhances the human antibody response to hepatitis A vaccination." Psychosomatic medicine 65.5 (2003): 831-835.

  • Benedict, Christian, et al. "Acute sleep deprivation has no lasting effects on the human antibody titer response following a novel influenza A H1N1 virus vaccination." BMC immunology 13.1 (2012): 1-5.

  • Prather, Aric A., et al. "Sleep and antibody response to hepatitis B vaccination." Sleep 35.8 (2012): 1063-1069.

  • Derek Lowe on COVID mutation and vaccine utility

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