Dosage is NOT proportional to weight

[tenshu2k]

LOL!
I see it like this, germans do think they drink the most but honestly any indian can buy 100 times the amounth of alcohol in one sitting than any regular german due having such fatter lined pockets 17,000$ a month...so based on that im going to say indians drink more becuz they can buy more so they get more fucked up.

there is some genetics behind it. europeans do have higher natural tolerance, and tolerance is also something thats built through continued drinking.

but yea. indians do whisky not beer, .

 

[Blazif07]

What I wanna know is... How does one figure out how many receptors they have in their brain?... I'm not gonna volunteer to have my brain sliced 'n diced just so I know how much I should theoretically take.....

 

[hansimglück]

Germans get beer for breakfast already as a child. Thats why they have such a large tolerance.

 

[sheepie]

I can't see how weight doesn't make a significant impact. More weight = more blood volume = more dilution of the drug throughout the bloodstream. I weigh 280lbs and I took one capsule for my first dose and felt nothing. Its hard for me to believe the effects weren't present because I had so many serotonin receptors in comparison to a 16 year old or for that matter my friends? I think it is because the drug was diluted in a large blood volume and was unable to reach an effective dosage level in my brain.

Receptor downregulation occurs when you abuse MDMA as well, and dosage goes up not down to achieve similar responses?

Dilution schmilution. What difference does it make if its diluted. You're not high because there's MDMA in your blood. You're high because the MDMA attaches to receptors in your brain.

Put it this way, say you have a circular tube of dirty water with a filter somewhere inside. Water is constantly being pumped and circulated through the filter. In this scenario, it's not the amount of dirt floating around through your water that makes you high, its the amount caught in the filter. So in this sense, a 2ft tube or 1ft tube won't make a difference. It's still going to get attached to the filter either way.

What I wanna know is... How does one figure out how many receptors they have in their brain?... I'm not gonna volunteer to have my brain sliced 'n diced just so I know how much I should theoretically take.....

There's probably some way of estimating... probably similar to biological age?

 

[mesial]

^^
From wikipedia:
"Binding affinity data alone does not determine the overall potency of a drug. Potency is a result of the complex interplay of both the binding affinity and the ligand efficacy. Ligand efficacy refers to the ability of the ligand to produce a biological response upon binding to the target receptor and the quantitative magnitude of this response. This response may be as an agonist, antagonist or inverse agonist depending on the physiological response produced. [3]"

Ligand binding efficiency is describe by the dissociation constant Kd. Kd is determined by molar concentrations of the ligand (MDMA). This efficiency is based on concentration, therefore if the same amount of substance is diluted more (1ft tube going to a 2 ft tube), its molar concentration is lowered and thus the Kd is affected.

There are many factors that affect dosage and weight is definitely one of them. Drug recommendations aren't published using weight for no reason.

 

[sheepie]

^ It seems that those only apply to "agonist, antagonist or inverse agonist" which makes sense.

In terms of LSD, Shrooms (agonists), it depends how much blood you have because less molecules will be hitting the receptors and not attaching. In this case, I can see how the Kd can come into play

However, MDMA works the same way as ritalin does on dopamine (which is the discussion I was having with my doctor), by preventing re-uptake. This isn't a "hit and run" molecule. It finds its parking space and stays there.

I'd like to make a note that everything I'm saying here is using logic of things I already know. My doctors arguments may be different. He is very respectable and specializes in this field.

 

[FrankieBonez]

Native americans and asians are believed to lack an enzyme in their liver's that helps break down alcohol.

http://alcalc.oxfordjournals.org/content/32/2/129.short

 

[Bearlove]

Erowid suggests


Oral MDMA Dosages
Threshold 30 mg
Light 40 - 75 mg
Common (small or sensitive people) 60 - 90 mg
Common (most people) 75 - 125 mg
Common (large or less sensitive people) 110 - 150 mg
Strong 150 - 200 mg
Heavy 200 + mg

I normally say to people that around the 120 mgs is the sweet spot for most people - obviously if your 3tf 60lb or 9ft 300lbs your going to need more / less.

 

[pnut3844]

I can't see how weight doesn't make a significant impact. More weight = more blood volume = more dilution of the drug throughout the bloodstream. I weigh 280lbs and I took one capsule for my first dose and felt nothing. Its hard for me to believe the effects weren't present because I had so many serotonin receptors in comparison to a 16 year old or for that matter my friends? I think it is because the drug was diluted in a large blood volume and was unable to reach an effective dosage level in my brain.

Receptor downregulation occurs when you abuse MDMA as well, and dosage goes up not down to achieve similar responses?

well im a fairly small guy around 130 and i have taken massive amounts of pills before and hung with my friends who are 180-220 so imo weight never played a factor. and it takes me at least 2 to get off now so yea im saying the weight thing is bunk

 

[liquidreality]

I would imagine that each persons ability to metabolize neurotransmitters would also play a role. If someone had a naturally higher concentration of MAO, or if their MAO is more efficient a slightly higher dose may be required. This is because if the serotonin is metabolized more quickly there would be less available to be taken into the neuron. Also, if someone had a higher concentration of CYP2D6 liver enzyme the dose would need to be boosted as well. This is due to the fact that a larger dose would be required to saturate the enzyme.

 

[Detrevni]

There's definitely more than one factor to contribute to MDMA's potency besides weight. If I were to speculate I would say that some of the main factors are tolerance, binding affinity, # of receptors, and then weight. Weight being lower on the scale than others.