Arnica

[jinx]

Originally Posted by TheMercenary

Acetaminophen (Tylenol) works by inhibiting the synthesis of prostaglandins in the central nervous system and peripherally blocks pain impulse generation through an unknown mechanism. It's antipyretic effect is due to an inhibiting action in the hypothalamus heat regulation center in the brain.

So you don't know either eh? Your answer was better than the one monster found on Tylenol's site.
The wiki pretty much sums up what a few minutes on google will tell you; no one really knows for sure. But it works, so people take it and give it to their kids, just like arnica. Except you can't damage your liver with arnica...

Mechanism of action

The mechanism by which paracetamol reduces fever and pain is still a source of considerable debate[citation needed]. The reason for this confusion has largely been due to the fact that paracetamol reduces the production of prostaglandins, pro-inflammatory chemicals the production of which is also inhibited by aspirin, but, unlike aspirin, paracetamol does not have much anti-inflammatory action. Likewise, whereas aspirin inhibits the production of the pro-clotting chemicals thromboxanes, paracetamol does not. Aspirin is known to inhibit the cyclooxygenase (COX) family of enzymes, and, because of paracetamol's partial similarity of aspirin's action, much research has focused on whether paracetamol also inhibits COX. It is now clear, however, that paracetamol acts via (at least) two pathways.[6][7][8][9]
The COX family of enzymes are responsible for the metabolism of arachidonic acid to prostaglandin H2, an unstable molecule, which is, in turn, converted to numerous other pro-inflammatory compounds. Classical anti-inflammatories, such as the NSAIDs, block this step. The activity of the COX enzyme relies on its being in the oxidized form to be specific, tyrosine 385 must be oxidized to a radical.[10][11] It has been shown that paracetamol reduces the oxidized form of the COX enzyme, preventing it from forming pro-inflammatory chemicals.[7][12]
Further research has shown that paracetamol also modulates the endogenous cannabinoid system.[13] Paracetamol is metabolized to AM404, a compound with several actions; most important, it inhibits the uptake of the endogenous cannabinoid/vanilloid anandamide by neurons. Anandamide uptake would result in the activation of the main pain receptor (nociceptor) of the body, the TRPV1 (older name: vanilloid receptor). Furthermore, AM404 inhibits sodium channels such as anesthetics, lidocaine and procaine.[14] Either of these actions by themselves has been shown to reduce pain, and are a possible mechanism for paracetamol, though it has been demonstrated that, after blocking cannabinoid receptors and hence making any action of cannabinoid reuptake irrelevant, paracetamol no longer has any analgesic effect, suggesting its pain-relieving action is indeed mediated by the endogenous cannabinoid system.[15]
A theory that held some sway, but has now largely been discarded, is that paracetamol inhibits the COX-3 isoform of the cyclooxygenase family of enzymes.[6][16] This enzyme, when expressed in dogs, shares a strong similarity to the other COX enzymes, produces pro-inflammatory chemicals, and is selectively inhibited by paracetamol. However, in humans and mice, the COX-3 enzyme is without inflammatory action, and is not modulated by paracetamol.[6]

[TheMercenary]

Mine was from memory.

I can draw you the COX enzyme pathways on a napkin if you like.

[jinx]

Memory from when?

[TheMercenary]

Originally Posted by jinx

Memory from when?

From when I went to school to study all that crap. Most of it was dumped after test after test after test after paper after research after test. Some stuff never goes away, the rest is like riding a bike, once you get on you it all comes back.

[jinx]

Acetaminophen and the Cyclooxygenase-3 Puzzle: Sorting out Facts, Fictions, and Uncertainties

Received February 24, 2005; accepted May 5, 2005.

Cyclooxygenase (COX)-3, a novel COX splice variant, was suggested as the key to unlocking the mystery of the mechanism of action of acetaminophen. Although COX-3 might have COX activity in canines, and this activity might be inhibited by acetaminophen, its low expression level and the kinetics indicate unlikely clinical relevance. In rodents and humans, COX-3 encodes proteins with completely different amino acid sequences than COX-1 or COX-2 and without COX activity; therefore, it is improbable that COX-3 in these species plays a role in prostaglandin-mediated fever and pain. The aim of this review is to evaluate the literature that seeks to point out critical theoretical and methodological limitations of the COX-3 studies that led several investigators to scientifically questionable conclusions....

In 2002, Dan Simmons' group reported the discovery of a new COX isoenzyme that was putatively the specific target of acetaminophen. The discovery of the so-called COX-3 as an acetaminophen-sensitive isoform seemed to solve the mystery of acetaminophen and attracted considerable attention, and several commentaries were published quickly in prominent scientific journals. This discovery in canines was generalized to humans and rodents without critical evaluation of the experimental data. Unfortunately, many in the scientific community now believe that the mechanism of action of acetaminophen is selective inhibition of COX-3; however, this hypothesis is not supported by experimental evidence. The aim of this review is to thoroughly evaluate the scientific literature with particular examination of the critical theoretical and methodological contradictions of the COX-3 puzzle.

[monster]

Originally Posted by jinx

the one monster found on Tylenol's site...

yebbut even GWB could explain in better than that.....while choking on a pretzel...

[jinx]

Im surprised there was no mention of fairy dust actually...

[monster]

Side effects, precautions, interactions of arnica

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When used frequently or for long periods, arnica can cause contact dermatitis or eczema. Some people may experience stomach discomfort, including nausea and vomiting. Liver and kidney damage has also been reported.


from here:

http://www.vitamins-supplements.org/...nts/arnica.php

:/

[jinx]

hey no shit... thanks.

[TheMercenary]

Yea, COX-3's were not even on the radar screen when I was in school.