This first edit is just my own writing. I'd have to go looking for the appropiate references, though they should be available in standard textbooks. --Seejyb 00:52, 10 August 2006 (UTC)
Hi Seejyb. I've changed your introductory definition hoping to reflect more clearly the IASP definition. And have removed "It is mostly a function of how healthy the pain nerves and central pain processing pathways are, and of the chemical milieu in the tissues which the nociceptors innervate" because, even a healthy peripheral and central nervous system which is experiencing pain in one sensory domain will modulate the threshold for another. Anthony (talk) 14:44, 2 September 2009 (UTC)
Just FYI: I'm going to go ahead and reference some of the info that has already been added. Also, I'm just going to add a quick blurb about threshold shifts. If something that I add is not scientifically correct, please don't hesitate to change it! Thanks! Hsh8 (talk) 17:25, 16 June 2009 (UTC)
Hi Hsh8. The blerb on threshold shift is interesting and I'd like to see it (and much, much more on pain threshold) here but I think it really should wait until someone has the time to reference it.
Pain threshold is commonly reduced by inflammation in the vicinity of nociceptors, such that normal touch becomes painful in the area of inflammation (allodynia). In such circumstances, the use of anti-inflammatory medications or physical therapies such as cooling or mild heat may return the nerve sensitivity or threshold to normal—it does not increase the threshold to above normal.
The use of morphine-like drugs does elevate the pain threshold (as well as pain tolerance). The same is true of a diverse number of other centrally acting analgesic drugs affecting pain relay neurons. Local physical techniques such as electrical stimulation, cooling or heat may temporarily increase the pain threshold.
However, short of damaging pain nerves—such as may occur in nerve injuries or neuropathies—the effects of interventions (pharmacological or physical) used to increase the pain threshold do not last much longer than the duration of their use.
Anthony (talk) 10:25, 8 September 2009 (UTC) I didn't write the above. Anthony (talk) 11:07, 16 October 2009 (UTC)