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Xherrus
19-02-2004, 11:17
Hi everyone,

I have been reading a bit about Loperamide (Imodium, an opiate used as an anti-diarrhoeal remedy) and apparently it does not cross the blood-brain barrier such that it causes a high in non-toxic doses. I also heard that Loperamide polistirex (the stuff bound to microscopic pieces of plastic, as "DXM polistirex") does cause a high and respiratory depression. I was wondering if there were any way to get around this obstacle, as it obviously has abuse potential since ppl have taken it with Codeine for an extra "weak Darvon-like buzz" (Coldwaterworld) and are rumoured to have converted it to Fentanyl.

My final idea relates to a case I read about on the internet and can't verify after searching again a lot, regarding a trick used to get the stuff through the BBB. A man was found (unconscious I think) in a car, with 2 boxes of Imodium and several mobile phones taped around his head.

What do you ppl think, should I borrow some of my friends' phones and give it a try with a much smaller dose of Imodium?

phase_dancer
19-02-2004, 13:44
Interesting stuff Xherrus, but I have to admit I have little knowledge in this area. If you don't get a reply I'll dig out the texts tomorrow and see if I can add anything worthwhile.

Kaister
19-02-2004, 13:48
I tried this once.
I filled a microwave oven with 60 packets of Imodium (still in their boxes, very important) and used 7 rolls of gaffa tape to strap it to the top of my head.
Then I got into a car (a convertible, very important for head space, if you can visualise it).
I was found the next day slumped in the front seat, apparently because of the oven, but I think it was because I didn't put my seat belt on!

Kaister
19-02-2004, 17:21
Some interesting reading...

Pharm Res 1997 Mar;14(3):325-328 Delivery of loperamide across the blood-brain barrier with polysorbate 80-coated polybutylcyanoacrylate nanoparticles.

Alyautdin RN, Petrov VE, Langer K, Berthold A, Kharkevich DA, Kreuter J

Department of Pharmacology, Sechenov Medical Academy, Moscow, Russia.

PURPOSE: The possibility of using polysorbate 80-coated nanoparticles for the delivery of the water insoluble opioid agonist loperamide across the blood-brain barrier was investigated. The analgesic effect after i.v. injection of the preparations was used to indicate drug transport through this barrier. METHODS: Loperamide was incorporated into PBCA nanoparticles. Drug-containing nanoparticles were coated with polysorbate 80 and injected intravenously into mice. Analgesia was then measured by the tail-flick test. RESULTS: Intravenous
injection of the particulate formulation resulted in a long and significant analgesic effect. A polysorbate 80 loperamide solution induced a much less pronounced and very short analgesia. Uncoated nanoparticles loaded with loperamide were unable to produce analgesia. CONCLUSIONS: Polysorbate 80-coated PBCA
nanoparti cles loaded with loperamide enabled the transport of loperamide to the brain.

PMID: 9098875, UI: 97253432

Life Sci 1983;33 Suppl 1:315-318 Loperamide: evidence of interaction with mu and delta opioid receptors.

Giagnoni G, Casiraghi L, Senini R, Revel L, Parolaro D, Sala M, Gori E

Loperamide was tested on electrically-evoked contractions using a series of "in vitro" isolated preparations, in comparison with morphine, met-enkephalin, beta-endorphin, ethylketocyclazocine used as representative agonists of mu, delta, epsilon, kappa receptors respectively. The IC50 of loperamide on myenteric
plexus longitudinal muscle of guinea pig ileum was found to be 1.90 X 10(-7)M and equal to that of morphine. The IC50 on mouse vas deferens was found to be 13.02 X 10(-7)M. In this tissue, loperamide resulted as active as morphine, but 54 times less active than met-enkephalin (IC50 0.24 X 10(-7)M). On the rat vas
deferens where, as expected, beta-endorphin was strongly active (IC50 1.38 X 10(-7)M), morphine exerted a stimulatory action within the range 10(-5)M-10(-4)M and loperamide was only poorly depressive. The Ke value of naloxone, a specific mu receptor antagonist, against loperamide in the guinea pig ileum was 3.83 nM, and in the mouse vas deferens was 82.87 nM indicating that
loperamide in the guinea pig ileum acts on mu receptors while in the mouse vas deferens on another opiate receptor.

PMID: 6319884, UI: 84116593

Discussion on P-glycoproteins
http://www.mhc.com/PGP/PgpMain.HTML

Drug delivery to the brain by P-glycoprotein inhibition.
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11014404&dopt=Abstract

Tramadol0r
08-09-2007, 14:44
In Germany we sucsessfully tried to use Chinin or Chinidine to make the BBB more permeable... You can see what i wrote down in another Thread!

Tramadol0r

Splatt
08-09-2007, 15:16
Drugs don't have to cross the BBB to work, there are receptors all through your body, they can still have physical effects, which can even change mind states because of pjhysical stimulation or sedation. ie. loperamide, GABA, or pseudoephedrine and even ephedrine.

Tramadol0r
09-09-2007, 13:25
Loperamid works on the peripheral receptors and that's the reason why it handles Diarrhoe... But psychotropical effects are also possible...

Tramadol0r

red_eyed_wonda
11-01-2008, 04:03
In Germany we sucsessfully tried to use Chinin or Chinidine to make the BBB more permeable... You can see what i wrote down in another Thread!

Tramadol0r
do you mean quinidine?
http://en.wikipedia.org/wiki/Quinidine

Concurrent administration of P-glycoprotein inhibitors such as quinidine with loperamide has been found to produce respiratory depression, indicative of central opioid action.