http://www.springerlink....ontent/r362405777578758/
So, mescaline and morphine seem to have a cross-tolerance.

http://toxipedia.org/display/toxipedia/Morphine
"To understand the power of morphine to affect the brain one should point out that the B-phenylthylamine unit, is also central to affecting the brain in hallucinogenic molecules as well. Morphine shares the unit with LSD and mescaline. Morphine and its analogues differ from hallucinogens because they have narcotic, pain relieving, sleep-inducing effects."
Is this how one can explain mescaline having a cross-tolerance to morphine, and mescaline's antinociceptive properties?

http://www.sciencedirect...b5c15067c913674439533e7c
While, mescaline and THC don't seem to have a cross-tolerance.

http://www.ncbi.nlm.nih.gov/pubmed/17603035
Chronic administration of morphine or THC produced antinociceptive tolerance to the respective drugs, whereas combination treatment did not produce tolerance.
So can I assume that mescaline does not control pain, the same way that THC controls pain?

http://en.wikipedia.org/wiki/Anandamide
THC most likely gets its antinociceptive from its effect on anandamide and the TRPV1 vanilloid receptor.

That's the first time I heard about that. That's interesting. Do any other hallucinogens have such a cross-tolerance with morphine?

Opioids and Hallucinogens
http://www.sciencedirect...45dafa98c30144d0e60fb4f3
www.angelfire.com/alt2/f...ucinogen_interaction.pdf
http://www.scribd.com/do...le-in-sensory-perception

Opioids and Salvia
http://www.members.shaw....salvia_kappa_opioid.html

Morhine and Anti-cholinergics
http://adsabs.harvard.edu/abs/1977Natur.267..452T

Morphine and Ketamine
http://www.sciencedirect...95b6f0615d3d64978210613f

Morphine and Ibogaine
http://www.ncbi.nlm.nih.gov/pubmed/9259010
http://content.karger.co...B/produkte.asp?doi=28246
http://www.springerlink....ontent/w02w117210420544/
http://biopsychiatry.com/ibogainenalox.htm

Morphine and MDMA
http://www.ncbi.nlm.nih.gov/pubmed/10814832
http://www.sciencedirect...6fe6280d4badf6a447b391ff
http://www.mdma.net/rats/antipain.html
http://grande.nal.usda.g...rences&therow=194230
http://cat.inist.fr/?aMo...cheN&cpsidt=20183844
www.lycaeum.org/research...rchpdfs/1989_crisp_1.pdf

Morphine and DMT
http://www.springerlink....ontent/l2364480lnh776v4/
http://www.opioids.com/misc/dalda.html
http://grande.nal.usda.g...rences&therow=160285
http://www.lycaeum.org/d...newlex&simple=simple
http://ajpheart.physiolo...nt/abstract/00193.2002v1

“...morphine... has been known that it is a natural endogenous neurotransmitter in higher vertebrates"
http://www.salviasource....-naturally-produce/?wap2

Should I change the title to this post?
Should it be moved to another section of the nexus?
You should see my face right now. It's a mixture of awe and joy. I love google.

They have a mild cross tolerance and a somewhat pronounced potentiation when taken together for a completely different type of experience than either alone. It is an excellent combination for healing sessions with patients in a lot of pain. as a purpose driven combination IMO it has a lot of potential for terminal patients and other chronic pain situations.
As a common analgesic low dose mescaline is mildly stimulating and non hallucinogenic at doses >100mg but is as effective on pain as 10mg of Oxy for me. But for days when pain reaches "severe" A 1/4 dose of tar and 30mg oral morphine will last all day long into the evening w/o feeling "doped" and keeping a good energy level as well as a good attitude.
Huge potential in analgesia and as a "cocktail" drug for a number of conditions
SB

serotonergics in general have antinociceptive properties.
tramadol has weak affinity for mu (o-desmethyl-tramadol has 100x the affinity), but is also a 5HT reuptake inhibitor. this latter activity gives it additional analgesic properties