Health Consequence
of Acetaminophen (Paracetamol,
APAP)
4/27/21 http://healthfully.org/rc/id5.html
1) The dug called acetaminophen (in the United States,
Canada, Japan, South Korea,
& Iran) is called paracetamol elsewhere. Sold for the relief
of pain[1],
fever, and headaches. Because of
aggressive marketing; it
is the most widely sold
over-the-counter drug, and is frequently added to prescription medications
especially opioids[2].
It is found in 100 over-the-counter
preparations plus 65 prescription opiates.
U.S. sales total over $1 billion annually. Because it is often abbreviated
as APAP (acetyl-para-amino-phenol)
on prescriptions
and bottles, this tragically fools
the user (see #4). Read on and you will
know why it’s slight benefits are not worth their many risks.[3]
2) Acetanilide was the first
aniline derivative
serendipitously found to possess analgesic as well as antipyretic properties,
and was quickly introduced into medical practice under the name of Antifebrin
by A. Cahn and P. Hepp in 1886. But its
unacceptable toxic effects, the most alarming being cyanosis[4],
prompted the search for less toxic aniline derivatives. Harmon Northrop Morse
had already synthesized
paracetamol at John Hopkins University in 1877, but it was not until 1887 that
clinical pharmacologist Joseph von Mering tried APAP on patients. However, its
precursor phenacetin became
popular. APAP, the metabolite of
phenacetin, was first marketed in the US in 1953, but took until the 70s for widespread
usage as an alternative to NSAIDs such as aspirin, naproxen and ibuprofen.
3) APAP’s peak absorption
30-60 minutes after
oral administration and its half-life is 2 hours. Dosing is 10-15 mg/kg every
4 hours, 5 doses
per day maximum. Recommend maximum dose
is 1,000 mgs, and 4,000 mg per day. Like
all NSAIDs, it blocks prostaglandins, thus it is anti-inflammatory drug, though
the opposite is believed.[5] Like NSAIDs, pain reduction compared
to a
placebo is slight & ineffective for acute pain. “Paracetamol is ineffective in
the treatment of lower back
pain and provides minimal short-term benefit for people with osteoarthritis” a 2014 metastudy
found.
4) Uninformed users presume it is safe like
aspirin and other NSAIDs, and thus will up the dosage as pain persists. APAP
is also added to a large number of prescription and over-the-counter medications;
thus, doubling the dosage. APAP is the
leading cause of drug acute liver failure (ALF)
in the U.S. My
cousin spent
10 days in the hospital in the summer of 2009; he took Vicodin and Tylenol. Dozens
of opioids contain APAP (Vicodin,
Darvocet, Percocet, at
Rxlist). APAP is in popular over-the-counter
drugs include Tylenol, Excedrin, Coricidin-D and Nyquil for which 30 ml has 700
mgs of APAP. In prescription drugs, it
is usually label as APAP; and thus 44%
of ALF patients took both prescription
and an over-the-counter drug. “Eighty-one
percent of unintentional patients [not suicide] reported taking acetaminophen and/or
other analgesics for acute or chronic pain syndromes… survival rate 65%.”
The authors of the study concluded: “..., acetaminophen hepatotoxicity far
exceeds other causes of acute liver failure in the United States. In the December
2005 issue of the medical
journal Hepatology, “the annual
percentage of potentially fatal acute liver failure (ALF) cases caused by acetaminophen
(TYLENOL) rose from 28 percent
in 1998 to 51 percent
in 2003.” In 2010, APAP
caused 56,000 emergency-room
visits, 26,000 hospitalizations, and 458 deaths.[6] Given the voluntary nature of side effect
reporting system, those figures are a gross underestimate, see Side Effect. A well designed study
using the biomarker for liver toxicity, alanine transaminase found that 39% of volunteers
experienced an elevation
of ALT[7]
more than 3 times the upper limit, and a quarter of that number had 8 times the
clinically significant level of ALT. The
reason is the CD44 gene found in 39%
of volunteers. One cause of toxicity is
through depletion glutathione
which is produced in the liver and is a cofactor in various liver reactions,
and a very strong antioxidant which protects the liver and other tissues, Wiki, at, and.
5) Paracetamol poisoning
“Intravenous
& oral formulations of acetylcysteine are available for the treatment of paracetamol (acetaminophen)
overdose.[8]
When paracetamol is taken in large quantities, a minor metabolite called N-acetyl-p-benzoquinone
imine (NAPQI) accumulates within
the body. It is normally conjugated by glutathione, but when taken
in excess, the body's glutathione reserves are not sufficient to inactivate the
toxic NAPQI. This metabolite is then free to react with key hepatic enzymes,
thereby damaging liver cells. This may lead
to severe liver damage and even death by acute liver failure. In
the treatment of acetaminophen overdose, acetylcysteine acts to maintain or replenish depleted glutathione
reserves in the liver and enhance non-toxic metabolism of acetaminophen” Wiki.
Another mechanism
is through the cytochromes P450 enzyme system which in the liver metabolizes
drugs including APAP—see Wiki. See
auxiliary for more on P450. If a drug or
certain fruits such as grapefruits utilize that pathway, then a toxic accumulation
can occur, especially in the 39% whose liver is sensitive to APAP; the same for
those with acute neuropathy (kidney disease).
APAP, the best-selling NSAID has
no significant benefits, causes well over 26,000 hospitalizations for liver
failure yearly, has serious chronic side effect, yet is sold over the counter,
and is the NSAID of first choice by most doctors, and is commonly added as a
second ingredient in over 165 prescription drugs: something is very wrong with
our corporate
medical system, education of doctors, and our regulatory systems. 5b) Glutathione and CO Q10: The
combination of down regulating the production of CoQ10 essential for the
production of ATP and downregulating glutathione one of the 3 most important
antioxidants, these effects are a major factor in the many consequences caused
by APAP. The ATP is the fuel which runs
all cellular processes. “It
is metabolized to a toxic intermediate
that is subsequently neutralized by glutathione before being finally excreted
in the Urine.” [8]
6) “In 1998 the decreased use of aspirin in
U.S. children was first suggested as a possible factor in the rising prevalence
of asthma.” Two years later it was
linked to the use of
APAP.
A study of 205,487 children age 6 to 7
years published
in Lancet found a 323% increase in risk of asthma for those with high use
group versus no use. “Use of paracetamol in the first year of
life and in later childhood, is associated with risk of asthma,
rhino-conjunctivitis, and eczema at age 6 to 7 years”
also meta-analysis
of 425,140 subjects. A similar large study
of teens came to the same conclusion. Another
study found that childhood asthma risk increased if APAP was taken during
pregnancy. Another
study of 322,959 children in 113 centers found for highest exposure a 2.51
increase. This review article describes
the mechanisms through inhibition of both leukocyte myeloperoxidase & of
GST role in lung growth. A
study in 2010 linked APAP to infertility.
An “Epidemiological studies have shown that acetaminophen by women
during pregnancy is associated with increased risk of cryptorchidism [absence
of testes] in boys” possible by lowering testosterone during the masculinization
programming window. This finding
is supported by studies on human and rat fetal testes. Developmental and behavior
affects have been
uncovered for APAP. In a
Norwegian study (Oct 2013) of 2.919 Norwegian mothers with same-sex
sibling pairs who were used to adjust for familial and genetic factors, they
found “substantially adverse development outcomes at 3 years of age…
[including] attention deficit hyperactivity disorder [ADHD} or language
disorder.… Poorer by comparison to sibling at 3 years of
age were motor gross motor development by 76%, communications by 80%,
internalizing behavior by 86%, higher levels of activity by 84%. This was for
mother who had taken APAP prenatal for more than 28 days;
and smaller effect for 1-27 days of APAP--similar
findings in another study. APAP is
associated with autism: “Acetaminophen use after measles-mumps-rubella
vaccination was significantly associated
with autistic disorder when considering children 5 years of age or less… when
considering only children who had post-vaccination sequelae (OR 8.23…)” at, also. A Danish pregnancy cohort
study of 64,322 consisting of 3 interviews followed by one at 6 months
after childbirth: “Research data suggest
that acetaminophen is a hormone
disruptor, and abnormal hormonal exposures in pregnancy may influence fetal
brain development.”
APAP use during pregnancy was by
the 7th year
associated with a 29% increased incidence of hyperactivity (ADHD) and its
severe form (HKD) 37% higher.“ A
link to its effect upon cognitive function
is through reactive metabolites which are linked with chemical and the
formation of senile plaque, a 1971
study found. These serious health
issues are ignored, thus pharma’s KOLs (key opinion leaders) who teach
physicians that APAP
is safe during pregnancy, for babies, and for children. It is even more dangerous
for adults because of its blockage of COX-2,
which increases the risk of clotting[9] and the production of atheroma thus MIs and Stokes.
7) At heart of the pathology
is APAP’s affect upon one of the essential antioxidants, glutathione (without its
babies die): “Paracetamol
damages the liver through the formation of a highly reactive metabolite which
is normally trapped and inactivated by preferential conjugation with hepatic
glutathione. Following an hepatotoxic dose, glutathione is depleted and the
toxic metabolite binds covalently to vital proteins and enzymes causing cell
damage and necrosis,” at 1983.
“Overdoses
are frequently
related to high-dose recreational use of prescription opioids, as these
opioids are most often combined with acetaminophen.[57]
The overdose risk may be heightened by frequent consumption of alcohol”, Wiki.
8) APAP wasn’t proven COX-2 inhibitor until 2008. “The
variance with other studies occurs because of method
of analysis whole cell versus broken cell preparation…. Thus, the myth
of APAP as a weak
prostaglandin inhibitor persists. [10] … maximal ex-vivo inhibitions were 56%
(COX-1)[11]
and 83% (COX-2)” at. Thus, APAP is a NSAID, and like all NSAIDS but aspirin they
increase the risk for ischemic events including strokes & MIs (heart
attacks). Allow
me to
go over briefly the COX-2 Vioxx
story. Vioxx was used in a trial to see
if it prevents Alzheimer’s disease like aspirin. The seniors given Vioxx
had over a 4-fold
increase in MIs, and thus the trial
was stopped early. An increase in heart
attacks didn’t show up in other trials is because Merck selected younger,
healthy volunteers. A warning letter by
the FDA resulted in the block-buster being “voluntarily being removed in Nov.
of 2004, but by then estimated 160,000 MIs occurred and 55,000 deaths. Sales
were $2.5 billion yearly. Unfortunately, the FDA left one COX-2
inhibitor on the market, Celebrex, though it was by then banned in Canada and
the EU. The panel which approved Celebrex
requested that its advertising be banned, but that was never enforced. For an
excellent account of the disaster Marcia Angell’s The Truth About the Drug
Companies, p 265-276. (Note
the Wikipedia article of 05
on Vioxx has been scrubbed, as too the one on Celebrex). “Use of NSAIDs
or acetaminophen at high frequency or dose is
associated with a significantly increased risk for major cardiovascular events”— AHA
2006. The AHA
warns that for all NSAIDs but aspirin[12] regular usage greatly increases incidence of heart attacks—see
FASEB (concluding
sentence).
9) So why is pharma so big on
acetaminophen? Think like a pharma
executive, thus business strategies are
measured by profit; I call this tobacco ethics.
A drug which causes an assortment of chronic
conditions is a winner, while one that prevent chronic conditions--such as
aspirin--is subjected to criticism based upon what I and others call tobacco
science. Many physicians found
out that the NSAIDs inhibit like Vioxx COX-2, therefore they cause MIs.[13] This entails that some doctors are hesitant
to recommend the long-term usage of NSAIDs.
Believing that APAP isn’t an NSAID, they are far more willing to prescribe
APAP than an NSAID such as Motrin or Aleve.
Here is where it gets ugly: A
doctor following treatment guidelines will prescribe for the typical patient
who has had a heart attacked patented drugs costing over $70,000 a year (for
high cholesterol, arrhythmia, three for hypertension, and an anticoagulant). APAP
is causal for asthma, coronary heart
disease, autism, ADHD, and hypertension; thus, billions are made treating side
effects of the leading NSAID, APAP. The FDA is an extension of big pharma
and APAP sales are over $1 billion annually.
The FDA’s advisor board in 1977 recommended
a packaging warning: “Do
not exceed the recommended dosage because severe liver damage may occur," but
what of all the evidence above for other conditions? This black box warning
was issued in in 2010. It took
until 2014 for the FDA to
request that manufacturers lower the
dose to 325 mgs (yes, a mere request). Acetaminophen’s
history is another example of pharma’s tobacco ethics which results in their
ability to influence the FDA, politicians, physicians, and the public. They
frame the practices of medicine through
their KOLs (key opinion leaders) treatment guidelines, medical textbooks, and continuing
education of doctors. Seeing through the
eyes of a pharma executive provides the best explanation of our drugged world; thus,
APAP is a blockbuster.
10). It is as Prof. Ben
Goldacre state, “The devil is in the
details.” This negative assessment is
of an industry that has consistently put profits before people and has
manipulated the practice of medicine to cause great harm; it is their business
model and their fiduciary duty. There is
a chorus of critics. Three things I highly
recommend: 1) to click on my collection
of YouTube documentaries (each with a short description) on bad
pharma. 2) To read Prof. Peter Gotzsche,
Deadly
Medicines and Organized Crime, How Pharma has Corrupted Healthcare. It
won a medical book merit award by
the British Medical Association, has a forward written by BMJ’s former editor-in-chief
and another by the JAMA’s Deputy Editor.
3) To click on link
and read my 5-page explanation as to Why
Physicians Give Junk Treatment. It removes the blame from physicians
who are
practicing medicine in a very corrupt system.
As Prof. Goldacre says: “A
perverse system produces perverse results.”
Goldacre is a founder of the AllTrials movement. Having uncovered a liar, much that goes around
as established “truths”, ain’t. Based on
personal experience & several hours searching the literature, I have come
to believe that NSAIDs lack significant analgesic effect. If you break a toe
and need relief, don’t
reach for an NSAID. Any reduction in
pain is through natural process, not through the NSAID—time heals.
[1] The
mechanism for pain reduction is through the reduction of inflammation by
blocking only
50% of COX2 & COX1 enzymes (prostaglandins), Goodman & Gilman’s
pharmacology textbook 2007 edition, p. 693).
Thus, APAP is a
“mild analgesics” p 681.
[2] The supposed agonistic
effect of APAP with opioids, assuming only moderate
publish bias is
purportedly due to the conversion of arachidonic acid that facilitate effects
of opioids on K+ channels.
However this causal relationship is far from established and PhARMA,
relying upon audience ignorance, has as their norm used bio-pathways to sell
their products to physicians. APAP
should not be included with opioid medications since most people will take an
opioid repeatedly until pain is reduced, and 39% are susceptible at much lower
doses to APAP’s toxic effect on the liver.
A number of nations have acted to limit this deadly cocktail.
[3] After years
of study, I found at the effort to protect the public is a façade; thus, I
don’t, and won’t put in my body unnatural chemicals called drugs, with a few
exceptions. Pharma does all it can to
burry what it knows, and the FDA is part of the regulatory façade.
[4] Cyanosis
is a blue or purple coloration of
the skin due to the tissues near the skin surface being low in oxygen.
[5] “One of the reasons
leading to such controversial findings may lie in the fact that acetaminophen
elicits no measurable inhibition of PG [prostaglandins COX-1 & COX -2] formation in broken cell
preparations but a profound suppression
in intact cells (54 & 82%). Despite these findings, acetaminophen is still
regarded as a weak inhibitor of peripheral COX-1 and COX-2 enzymes” at.
[6] This is based upon
a
very, very imperfect reporting system where the side-effect from sent to the
FDA is forwarded to the drug manufacturer, and eventually after evaluation a
report totally side effects is sent to the FDA.
Because it is contrary to the manufacturer’s fiduciary obligation to
accurately report issues with their drugs, this method is designed to fall
short, see my article. Side Effects
rarely cause a drug being removed from the market until it goes off patent, and
black box warning have little effects. The
number of deaths given ratio of hospitalization involving liver failure (all 26,000)
to death is a gross underestimate given the minimal effectiveness of treatment,
and thus the progress to fatal liver failure—the damage is not reversible with
drugs.
[7] Alanine aminotransferase (ALT) is used to monitor liver toxicity. In this study of 14 days of 145 volunteers,
39 received a
placebo, and of the remaining 106 volunteers 38
had greater than 3 fold increase of ALT, of them 27 had 5 times the upper
limit, and 8 had over 8 times the upper limit.
The study’s ranging in age from 18 to 45—older people would
be at greater risk. The volunteers received
4 grams (the maximum recommended dosage).
The intended duration of the
study was 14 days. The author commented
that their review of previously published studies supported their observations.
Worst Pills Best Pills Newsletter article September, 2006, also
published at http://healthfully.org/nsaids/id8.html.
[8] Lee Know, Mitochondria
and the future of medicine, P 97
[9] “On the other hand, PTGS2 (COX-2) is a
more important source of prostaglandins, particularly prostacyclin which is
found in blood vessel lining. Prostacyclin relaxes or unsticks platelets, so
drugs that block this mechanism - like Celebrex (celecoxib) and other coxibs
(Rofecoxib) - increase risk of cardiovascular events due to clotting” Wiki.
[10] One of
the reasons
leading to such controversial findings may lie in the fact that acetaminophen
elicits no measurable inhibition of PG formation in broken cell preparations but
a profound suppression in intact cells. (7) .
Despite these findings,
acetaminophen is still regarded as a weak inhibitor of peripheral COX-1 and
COX-2 enzymes (2)--at.
[11] A 56% inhibition of
COX-1 is insufficient to block thromboxane, and thus prevent the platelets from
forming clots. Thus, blocking COX 1 prevents clots, while COX-2 blocking
promotes clots (see #7), and blocking just COX-2 thus promotes clots, and thus
MIs.
[12] “The Serhan’s group showed that
acetylation of
COX-2 by low dose aspirin leads to its biosynthesis of 15R-hydroxyelcosatetraenoic
acid. This intermediate is then
converted by transcellular metabolism to the anti-inflammatory lipoxin 15-epi-lipoxin
A4 in leukocytes’--AHA, and.
This distinguish aspirin from other NSAIDs by the production of lipoxin
[13] Oddly they believe
as
told by KOLs that for Celebrex and Aleve (naproxen) the risk is small based on
very week evidence the same for and APAP. Simply put (Harvard Prof. Marcia
Angell, pharma isn’t in the education business!”)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Non-technical summation
Acetaminophen (Paracetamol, APAP): It is the most widely
sold
over-the-counter drug for the relief of pain[1], fever,
and headaches. It is found in
over a 100 over-the-counter of
which 65 are with an opiate. As a
mild analgesic APAP’s inclusion with an opiate cannot be justified given its
severe side effect of causing live damage.
The
annual percentage of potentially fatal acute liver failure (ALF) cases caused
by acetaminophen rose from 28 percent in 1998 to 51 percent in 2003. A major cause is that acetaminophen is indicated
as APAP on most opiate prescriptions and the common use of the over-the-counter
Tylenol as a second drug for relieve of pain.
In a well-designed study it was found that 39% of those taking the
recommended dosage of APAP had 3 to 8 times the upper limit for ALT a marker
for liver toxicity. APAP in 2010 caused 56,000
emergency-room visits, 26,000
hospitalizations and 1,600 liver failures, and this is based on a system
designed to grossly underestimate the severity of the problem. New FDA limits
and warning goes into
effect in 2014. A study of 205,487
children age 6-7 found that the use of APAP is associated with a 323% increase
in the risk of asthma. The medical
literature on liver toxicity goes back to the 1960s. Aspirin at 975 mgs to start
and as needed
thereafter is a much safer and more effective choice. Development al and behavior affects have been
uncovered. In a
Norwegian study (Oct 2013) of 2.919 Norwegian mothers which same-sex sibling pairs who
were used to adjust for familial and genetic factors, they found “substantially
adverse development outcomes at 3 years of age… [including] attention deficit
hyperactivity disorder or language disorder. … Poorer by
comparison to sibling at 3 years of age were motor gross motor development by
76%, communications by 80%, internalizing behavior by 86%, higher levels of
activity by 84%. This was for mother who
had taken APAP prenatal for more than 28
days; and smaller effect for 1-27 days of APAP--similar
findings in another study. APAP is
associated with autism: “Acetaminophen
use after measles-mumps-rubella
vaccination was significantly associated with autistic disorder when
considering children 5 years of age or less… when considering only children who
had post-vaccination sequelae (OR 8.23…)” at, also. A Danish pregnancy cohort
study of 64,322 consisting of 3 interviews followed by one at 6 months
after child birth: “Research data suggest that acetaminophen is
a hormone disruptor, and
abnormal hormonal exposures in pregnancy may influence fetal brain
development.” APAP use during pregnancy
was by the 7th year associated
with a 29% increased
incidence of hyperactivity (ADHD) and its severe form (HKD) 37% higher. Though
believed to not be an NSAID, and thus
not to significantly inhibit the COX-1 and COX-2 prostaglandins, APAP does
based on whole cell assays. Thus APAP is
an NSAID and like NSAIDs increases incidents of ulcers and heart attacks
(aspirin is the exception). Aspirin is
the only NSAID whose benefits are greater than the side effects.
[1] The mechanism for pain reduction is through the reduction of
inflammation by blocking only 50% of COX2
& COX1 enzymes and
inhibiting the production of prostaglandins (Goodman & Gilman’s
pharmacology textbook 2007 edition, p. 693).
This is why in they are classified as “mild analgesics” (G & G at
681). A better method of assaying
places the inhibition of COX 1 at 54% and COX-2 at 82%, see footnotes 4.
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