• N&PD Moderators: Skorpio | thegreenhand

NMDA antagonists for tolerance, a collection of the evidence and anecdotal reports

I have used GHB quite excessively in the past and wonder if a NMDAR-agonist regimen might repair any possible damage. Also, I take 120 mg's of methylphenidate daily for adhd.. I have been doing so for about six months now and feel it is getting less effective. I am thinking about trying this but I'm not certain. All the NMDAr-agonists seem to have some serious setbacks. Also, the anecdotal reports provided by MeDieVil say that it's is probably not really effective for MPH tolerance..

I've never taken DXM but for some reason it rubs me the wrong way, can it be safely taken with my meds? I would use ket or nitrous but I don't want to get high, I haven't used any recreational drugs in a long time and I would like to keep it that way. Maybe I should get some Xenon :p


edit: should I stop taking my meds while on dxm? I am thinking of taking 120 mg of dxm for ten days.. I can buy XR caps with 30 mgs and plan to take 2 in the morning, two at night.. I don't like the idea of not taking my meds though..
 
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You needn't get high using ketamine, you're not supposed to feel the effect, and you can continue your medication while using DXM.
 
Okay, great. Are there any reports on methylphenidate tolerance and DXM or Ket?

Is it about total volume or what? Is one or the other more effective? I have a good source for cheap ketamine so it might be more price effective then dxm. A gram would cost me as much as a 10 day supply of dxm.. What would oral dosages be, and how effective is the first pass metabolite norketamine?

I just want to look at all the options.. taking for instance 50mg's of ket (oral!) a day seems less unhealthy and cheaper then taking 120mg's of dxm a day..


edit: I've looked for reports and couldn't find what I was looking for.
 
Looks like youll be the first trying it for ritalin, they work for stims since they upregulate D2 and D3 in the striatum wich should also work for ritalin's tolerance, you can keep on taking the ritalin with the DXM altough a break with dxm only would likely work better to reverse an allready existing tolerance.

Keep us updated
 
Well I have felt it the past few days - the memantine levels finally dropped and I haven't been taking Delsym. I was experimenting to see if the withdrawals would come - and they did. I had to go back to 20mg of Valium yesterday and I've been having to take it earlier.

Back to Delsym tonight. I'm going to do a 180mg "attack" dose tonight before I take my night dose, then do another 180mg with my afternoon Valium dose, then go down to 120mg twice a day for a few days, then down to 60mg twice a day maybe on day 10.

Whoever says that its a placebo thing doesn't know what they're talking about at all - even my pharmacist knows about the use of dextromethorphan for opiate and benzo tolerance reduction. LOL!

Anyway, yeah, I feel like crap now that the memantine has bottomed out. Its about perfect timing too.

I'm glad to have that poison out of my system though. The respiratory suppression, weird pulse issues (sometimes stimulants increased my pulse a LOT more than usual, other times it decreased, once it stayed the same - hallucinogens, including shrooms, caused abrupt heart rate increases but I have since shroomed after I ceased the memantine and the issue is no longer there), and the really jacked up head feeling ---- not worth it. Delsym at the doses I take is more expensive than where I got my memantine but its more easily accessible and it doesn't cause any of the problems that PCP and memantine do with my cardiovascular system. Ketamine causes tachycardia but no respiratory suppression with me - and ketamine only tends to cause tachycardia when I quite simply just do too much.

Anyway, don't give up - Delsym and memantine are both extremely effective. To be honest, I would think that taking your full Delsym dose all at once instead of twice a day would probably still be quite effective as I've heard of successes with regular dextromethorphan taken only twice a day.
 
^^^^^So your benzo tolerance dropped after taking DXM, also at what dose of DXM did you take & for how long? I have been taking 60mg twice a day with my Xanax. Today will be day 6 of taking DXM & Xanax
 
What form of DXM are you taking? The polisterex (Delsym) is what I've used. I was using 120mg twice a day when I first started taking it and by day 3, I knew I could cut my Valium dose because I'd take my full dose and pass out cold. That is pretty much the queue for me that its time to drop the dose a bit.

I honestly question whether or not standard DXM HBr will work as well or not - it gets metabolized into DXO much more rapidly than the polisterex formulation does. This is why a lot of people don't like tripping on Delsym. Even at double the dose of what they would normally take of an HBr formulation, they still never really get to the intense peak of the DXM experience and rather hit a plateau and stay there for a LONG time.
 
What form of DXM are you taking? The polisterex (Delsym) is what I've used. I was using 120mg twice a day when I first started taking it and by day 3, I knew I could cut my Valium dose because I'd take my full dose and pass out cold. That is pretty much the queue for me that its time to drop the dose a bit.

I honestly question whether or not standard DXM HBr will work as well or not - it gets metabolized into DXO much more rapidly than the polisterex formulation does. This is why a lot of people don't like tripping on Delsym. Even at double the dose of what they would normally take of an HBr formulation, they still never really get to the intense peak of the DXM experience and rather hit a plateau and stay there for a LONG time.

So you took 120mg all up in one day or 240mg all up in one day?
 
I would switch to Delsym. Its more expensive but if you're doing regular Robitussin, you need to take 4-6 doses a day to try to maintain plasma levels and even then, I really think the DXO conversion just happens too fast.
 
So you took 120mg all up in one day or 240mg all up in one day?

I took 120mg twice a day. Didn't get any psychoactive effects to speak of if you're worried about that. It was overkill but I wanted to get my tolerance going down fast and I'm pretty familiar with the safety profile of DXM, having taken 800+mg of the HBr form at least 5 days a week for about a year and stopping with no issues during or after.
 
I don't think it's available in Australia but i'll continue with Robitussin & keep people updated
 
I took 120mg twice a day. Didn't get any psychoactive effects to speak of if you're worried about that. It was overkill but I wanted to get my tolerance going down fast and I'm pretty familiar with the safety profile of DXM, having taken 800+mg of the HBr form at least 5 days a week for about a year and stopping with no issues during or after.

That's alot of that shitty syrup but i'll give it a go
 
Not worried, used to take it all the time then i lost the magic so gave up. Just want my Xanax tolerance to drop
 
I would do 60mg 4 times a day and see how that does for you. A higher dose still isn't really going to slow down the DXO conversion and elimination by much.

How many times a day do you take your Xanax? What I would do is take it with every Xanax dose you take at 30-60mg at a time. DXO definitely lasts longer than Xanax does so maybe if you can get a consistent blood level around the time you're actually taking the Xanax, it will work. I can't see regular DXM being effective for something like Klonopin or Valium but for Xanax and Ativan it should work if you dose at the same time you take your Xanax pills.
 
I would do 60mg 4 times a day and see how that does for you. A higher dose still isn't really going to slow down the DXO conversion and elimination by much.

How many times a day do you take your Xanax? What I would do is take it with every Xanax dose you take at 30-60mg at a time. DXO definitely lasts longer than Xanax does so maybe if you can get a consistent blood level around the time you're actually taking the Xanax, it will work. I can't see regular DXM being effective for something like Klonopin or Valium but for Xanax and Ativan it should work if you dose at the same time you take your Xanax pills.

I take Xanax roughly three times a day. The last few days i've been able to keep to 6mg Xanax throughout the day. I will try lowering my Xanax dose tomorrow and see how i go.

I take 60mg DXM in the morning before i dose Xanax & about seven hours later take another 60mg DXM.

Also, has anyone experienced a reverse in their tolerance to the sedative effect only & not prevent tolerance to the anxiolytic effects?
 
Looks like youll be the first trying it for ritalin, they work for stims since they upregulate D2 and D3 in the striatum wich should also work for ritalin's tolerance, you can keep on taking the ritalin with the DXM altough a break with dxm only would likely work better to reverse an allready existing tolerance.

Keep us updated

Right, and the striatum is hypothesized to be involved in sustained and selective attention right?

My tolerance has mostly occured in the sustained and selective attention area... hyperactive symptoms have also increased but not so much.. Impulsiveness seems to not have been affected, has been down ever since starting the meds.. I have read the research that MPH is not better then placebo after 25 weeks and it scares me because I'm starting to have the same old problems again..

So, what do you think... ket or dxm? ket would be taken orally so It'll actually be norketamine. I would consider memantine but a certain indian supplier doesn't ship to the Netherlands because of customs-problems. Stopping my meds is possible for about ten days so I have a window..

Also, the DXM I can get is sustained release, caps of 30 mg... Is there some need for High plasma levels? In that case I might do 90 mgs twice a day..
 
I honestly question whether or not standard DXM HBr will work as well or not - it gets metabolized into DXO much more rapidly than the polisterex formulation does.

Which is more desireable though, since DXO is also listed as an "uncompetitive channel blocker", same as DXM is on this list of NMDA receptor antagonists: http://en.wikipedia.org/wiki/NMDA_receptor_antagonist

And, "dextrorphan is much more potent of an NMDA receptor antagonist and much weaker as a serotonin reuptake inhibitor in comparison": http://en.wikipedia.org/wiki/Dextrorphan

I'm not clear if what we're looking for are is to blast the neurons with repeated strong doses of potent NMDA antagonists, or sustained plasma levels, or if both are needed. (or do we really know and are just speculating?)




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Another thing NMDA antagonists have potential for is turning certain addictive meds into sustainable long term treatments for mental disorders such as opiates and amphetamine's, normally they cant be used for that since tolerance will occur rapidly, however it may just be easier to counteract those issues rather then coming up with new novel compounds.

I like the quote someone put here before, NMDA antagonists certainly arent the magic bullets, however they are the next best thing after the magic bullets.

I'm pretty sure I remember reading that glutamate is heavily involved in fear extinction so maybe it's not a good treatment for anxiety. I still use opiates in combination with dxm to allow self medication with less unfortunate effects like tolerance and heavy dependence. Nothing treats my anxiety and depression so effectively. Eventually if I want my life to go anywhere, I might have to reconsider this method of treatment. If only I had adequate money, I could medicate and go to college.
 
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I've been taking ~30mg of DXM HBR every other day (seeing the effects on the gastrointestinal tract in the morning), and about to start taking it everyday starting tomorrow. I'm taking 45-90mg of adderall a day, and am hoping it'll cut down the tolerance back to 30mg a day. I'll be taking a 2 week break from amps to also aide in the tolerance lowering.
 
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