Can someone translate this? arachidonic acid and acetaminophen

  1. Can someone translate this? arachidonic acid and acetaminophen

    I am trying to figure out if, while taking arachidonic acid, one can take tylenol as needed for a headache. I seem to remember when ArA was new a few yrs ago there were some risks or at least comments on the topic, but I can't find them.

    I searched online and found 2 pages which discuss the two together but I can't understand if these should never be taken together or what the point is.

    Any help?

    Here is the product info page:

    TYLENOL® (acetaminophen) Pharmacology -

    And here it says:

    Mechanism of Action


    Although the exact site and mechanism of analgesic action is not clearly defined, acetaminophen appears to produce analgesia by elevation of the pain threshold. The potential mechanism may involve inhibition of the nitric oxide pathway mediated by a variety of neurotransmitter receptors including N-methyl-D-aspartate and substance P.

    Investigations indicate that endogenous pyrogens produced by leukocytes cause an elevation of prostaglandin E (PGE) in the cerebrospinal fluid. Fever results when the elevated PGE acts on the preoptic area of the anterior hypothalamus to decrease heat loss and increase heat gain. Acetaminophen has been shown to inhibit the action of endogenous pyrogens on the heat-regulating centers in the brain by blocking the formation and release of prostaglandins in the central nervous system. Inhibition of arachidonic acid metabolism is not requisite for the antipyretic effect of acetaminophen. Acetaminophen does not depend upon the activation of the arginine vasopressin V-1 receptor to induce antipyresis as has been noted in rats treated with indomethacin and salicylates. This has been demonstrated in animals by observing a decrease in both fever and PGE activity following administration of acetaminophen to unanesthetized cats, and in rabbits and dogs when brain prostaglandin synthetase was inhibited by the administration of acetaminophen.

    I also found this study: - European Journal of Pharmacology - Attenuation by acetaminophen of arachidonic acid-induced coronary vasolidation and output of prostaglandins in the isolated rat heart

    Attenuation by acetaminophen of arachidonic acid-induced coronary vasolidation and output of prostaglandins in the isolated rat heart

    Which says:

    We studied the effect of acetaminophen on the vascular actions of arachidonic acid and on the output of prostaglandins in the isolated rat heart. Arachidonic acid (33 nmol), administered as a bolus into the heart through the aortic cannula produced vasoconstriction followed by a long lasting vasolidation. Arachidonic acid also markedly increased the output of PGE2 and 6-keto-PGF from the heart. In the presence of acetaminophen (0.1–1.0 mM) both the output of prostaglandins and the duration of the coronary vasolidation were attenuated. We suggest that the major component of arachidonic acid-induced coronary vasolidation is mediated through prostaglandin synthesis and is blocked by acetaminophen.

    I also read the following which essentially (to me) said that taking acetaminophen will block the ArA from working properly. That's fine, I don't plan on taking it regularly, but want to know if it is bad or toxic to take both:

    Case in point: a classical study conducted by Dr. Todd Trappe at Ball State University (10) examined the effects of whole-body protein synthesis in 24 males receiving either the maximal over-the-counter doses of COX-2-specific inhibitors (which blunt arachidonic acid to prostaglandin biosynthesis) including ibuprofen (1,200 mg/day), acetaminophen (4,000 mg/day), or a placebo after completing 10-14 sets of 10 eccentric leg extensions at 120% of each participant's concentric one-repetition maximum.

    Interestingly, twenty-four hour post-exercise intramuscular protein synthesis rates increased 76% in the placebo group whereas protein synthesis remained unaltered in the two groups receiving ibuprofen or acetaminophen.

    Similarly, a 24-hr post-exercise elevation in intramuscular PGF2a levels in the placebo group (+77%) in comparison to the ibuprofen (-1%) and acetaminophen (-14%) groups was observed. This study seemed to provided the first compelling evidence for the involvement of arachidonic acid and PGF2a in muscle protein synthesis.

  2. This is actually an interesting topic. Data on acetominophen's MOA is mixed (COX-3, anyone?), but many believe that it inhbits COX-2 which does not bode well for downstream PGF2a synthesis. I hope madchemist is around here because he is VERY well-read on the arachidonic acid cascade.

Similar Forum Threads

  1. D-Aspartic Acid, Arachidonic Acid and Inhibit-E
    By liftsalot in forum Supplements
    Replies: 5
    Last Post: 06-26-2011, 07:51 AM
  2. arachidonic acid
    By tnubs in forum Nutraplanet
    Replies: 42
    Last Post: 07-11-2010, 12:51 PM
  3. Arachidonic Acid
    By angelo212 in forum Supplements
    Replies: 9
    Last Post: 04-30-2009, 05:11 PM
  4. Arachidic Acid vs. Arachidonic Acid?
    By Beige in forum Supplements
    Replies: 4
    Last Post: 03-06-2007, 01:56 PM
  5. Arachidonic Acid
    By soj in forum Nutraplanet
    Replies: 19
    Last Post: 11-20-2006, 07:07 PM
Log in
Log in