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Osmotic concentration and snorting

Doclad

Bluelighter
Joined
Mar 17, 2015
Messages
415
Hello everyone.

When it comes to taking stimulants that require low doses (amphetamine, hex-en and isopropylphenidate mostly) I like to do it by nasal route. The fact is that I use a nebulizer to reduce the damage caused to thenasal mucous and improve the bioavailability of the medication by segregating it evenly over the entire surface.

What I've not managed to avoid is pain. It hurts less than directly snorted, but it still hurts a lot. I have used distilled water solutions with Lidocaine HCl (20mg) to counteract this side effect but it does not do much for me, and it numbs my throat and I do not like it.

I think I read somewhere that osmolarity can play an important role in all this. I understand that it has to do with the osmotic pressure in the cells of the mucous membrane and the physical properties of the substances, and that add the right amount of NaCl to the solution can markedly reduce the pain. Is there any way to know if the pain is due to osmotic pressure or is it due to the causticity of the substance? If someone can explain this fact more deeply I would be very grateful.

Definitely, I would like to know what amount of NaCl I need to add to my solutions of 20mg/ml of Amphetamine, HEX-EN and Isopropylphenidate respectively, and if this balance can guarantee the reduction of pain in any case.

If someone can throw some formula for the calculation it would be great.

(Perhaps the thread fits better in the sub-forum "Neuroscience and Pharmacology Discussion". Put it there if you think it necessary, please).


DocLad
 
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The pain is because both those substances are vasoconstrictors, reducing blood flow to the area, and are also slightly acidic, and nasal use usually requires high concentrations, mixing lidocaine in is simply masking the damage.

Adding salt won't necessarily help as the dissolved solutions of drugs act as a salt already (the drug dissociates into e.g. protonated drug molecules and chloride ions). So depending on concentration, you may already be hypertonic (too much salt).

Lowering the concentration so you need to use more solution and/or switching to rectal use (which also allows a lower concentration) may alleviate some of this (rectum is substantially larger and is designed to absorb fluids unlike the nasal mucosa)

Adjusting the pH could possibly help too, but be wary of precipitation of the free base if you fiddle with it too much.
 
So, what concentration mg/ml would be the most correct for these substances in particular? How do you do the calculation?
The mg/ml concentration can influence in the % of absorption and his bioavailability?


DocLad
 
The concentration doesn't effect BA or absorbtion really, there is no "correct" concentration. Reducing concentration might help but don't expect a panacea.

If you want to match osmolarity to saline (which is 0.9% salt in water) then aim for a solution of about 0.15 mol per liter.
 
Where did you read the bit about osmotic pressure? I wouldn't mind looking at that myself.

Yeah, it's been said that preloading the sinuses with a splash of water helps, and although I can never remember to do this when I find myself about to snort something I know is gonna hurt, I do remember trying it and I can say that it DOES help, a lot. Tell us if saline helps even further, if you could.

I know little of the pH of those cathinones, but following a taste test of the them I can agree that they also taste like shit, and it has nothing to do with them being sour. In fact meth runs a pH of ideally 7, with 6 being about the lowest acceptable number, and if your amphetamine is HCl then I assume this to be the same (sulphate I have no idea). But the taste test I think confirmsa thing or two about vasoconstriction, which is more a characteristic of the compound's astringency: it directly causes all tissues to contract themselves on contact, much the way an unripe persimmon would. Astringency is neither bitter nor sour but its own special thing, and it's what we taste when we put these nasty things to our tongues. The notion is a bit out of our reportior nowadays unless you're into culinary stuff or western herbal medicinal but it's very real and I think better describes the notion you mean Sekio by vasoconstriction.

Lemme get off topic and agree that rectal is the way to go, though after years of experience I can say that there's no guarantee it might not induce the same thing in your colon, where your body can compensate in under a minute by triggering peristalsis and fill up that last part of intestine between sigmoid and rectum, diluting your plug at the very least, and causing a bowel movement at the most. The two reactions can happen within hours of each other using the same substance, and still it confuses me, since it would be like snorting a line of speed one day and feeling the burn, then doing the exact same amount again the following day or even four hours later and not noticing it at all. Weird.
 
Well, I just found it. Sekio said the following around 2015:

"... I have built up a spreadsheet to figure out osmolarity too.For a nasal spray the optimum concentration for ethylphenidate is 42 mg / mL. Any less than that and you will need to add some salt as well to ensure there's the same "osmotic pressure" in the spray as there is in your nose and tissues.
For instance at 10mg / mL ethylphenidate HCl solution will also need 6.7 mg / mL sodium chloride in it as well, or it will be irritating.
20 mg / mL ethylphenidate HCl needs 4.6 mg / mL salt.
30 mg / mL ethylphenidate HCl needs 2.6 mg / mL salt ... "

This is the thread:
http://www.bluelight.org/vb/threads...henidate(EPH)-or-Isopropylphenidate-(IPPD-IPD

As a result of this publication I opened this thread to expose my doubts about the concentration mg / ml of Hex-en, IPPD and amphetamine. Although the interesting thing is to know how the "spreadsheet" has done. In a comment above it says the following: "... If you want to match osmolarity to salt (which is 0.9% salt in water) then aim for a solution of about 0.15 mol per liter ..."
I guess this is the procedure, right? or not?

In any case, my intention was to eliminate the pain by following these steps, although now I have many doubts about its effectiveness since other variables play an important role.

Any other idea?


DocLad
 
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Seiko, could you tell me how you did the calculation with Ethylphenidate so that I can do it with other substances?

Thank you


DocLad
 
The idea is you want to match the molar concentration of the ions to be the same as the concentration of ions in 0.9% saline solution. Given that most drugs are HCl salts that dissociate into the same number of ions as salt does (2) then it's easy math, just aim for the same molarity as 0.9% salt water. If you are rusty on your high school chemistry here's how you work it out.

0.9% salt in water = 9 grams per 1000mL = 9 grams/liter
M.W sodium chloride = 58.4 grams/mol.
9 grams/L / 58.4g/mol = 0.1541 mol/L
MW ethylphenidate = 247.33g/mol + MW HCl 36.5 g/mol = MW of EPH.HCl 283.83 g/mol
283.83 g/mol x 0.1541 mol/L = 43.73 g/L ethylphenidate HCl.
43.73 g/L = 43.73 g per 1000mL = 43.73 mg/mL is the amount needed to make a slution with the same tonicity as physiological saline.

If you're using a mixture of salt and EPH; the concentration of both should add up to 0.1541 mol/L
so 30 mg/mL ethylphenidate HCl = 30g / L = 30 g/L / 283.83 g/mol = 0.1057 mol/L
0.1541 mol/L - 0.1057 mol/L = 0.0484 mol/L salt needed.
0.0484 mol/L * 58.4 g/mol = 2.8266 g/L salt needed = 2.8266 mg/mL = 2.8266g / 1000mL = 0.28266% salt needed in addition to the ethylphenidate
 
Well, this is the answer I was looking for from the beginning.

Thank you very much Sekio.


DocLad
 
Shit, that's interesting stuff Sekio, thanks.
lemme try to get back to that tomorrow, but what would u say about the ionic irregularities in substances in which pH is off of neutral? say hypothetically that my meth nasal spray, which has been working, mind you, since reading this thread (100mg/1.5mL) I now only realize has a pH of 6, using dH2O of course. How does one compensate or control the molar density of the additional HCl? How does one calculate mass based off of pH in a given solution in the first place? (this is about as far as my high skool chem goes). Add more water based on the heaviness of HCl-heavy meth? Or maybe it DOESN'T matter?

I'll try and get back to this later when I've time to focus.. But thanks for posting that.
and I will add that yah, meth hcl + water makes an effective nasal spray, salt or no salt.
 
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