Combinations - Quetiapine (Seroquel) + Lisdexamfetamine (Vyvanse)

[ThusSpokeZarathustra]

Swim took this combination today. He took three 30mg Vyvanse capsules (an amphetamine comparable to dextroamphetamine, etc.) around 7:00AM, and two 25 mg Seroquel around 10:00AM. Swim knew little of the effects, but enjoyed the combo slightly (especially for a buzz during class).

Swim has 3 questions.

1.) Swim knows combining uppers and downers is never a good idea, but these are pretty weak dosages (though SWIM is completely intolerant to Seroquel). Swim was just wondering what kind of negative physiological effects this can have on him? He says he felt very odd during the come up of the Seroquel, like a body buzz or even almost a numbness, for lack of a better word.

2.) He also felt that his pulse rate was a bit higher, but doesn't know how to read his pulse to differentiate between what he felt and what is normal or safe. If someone could clear this up, or let SWIM know how to read his pulse and decide if it's normal or not, that'd be cool. SWIM could probably just google it, but since it's drug related physiological question, I felt this was an appropriate place.

3.) Lastly, do any other swimmers get recreational value from Seroquel? swim couldn't tell if it was psychosomatic or what . . . because the amphetamines still worked perfectly during his lectures. If so, what is your recommended dosage for a seroquel noob? Is 50 mg drastic? His friend that hooked him up said his first time he railed near 400 mg. Sounds like bullshit though.

oh, and speaking of railing them; higher bioavailability? swim swallowed them, and also read somewhere that Quetiapine's oral bioavailability is 100%, so he didn't see much purpose in it.

[Felix Guattari]

1) quetiapine is thought to be a dopamine (D1 and 2), serotonin and norep. antagonist, which means, in theory, that it would cancel out most of the effects of the amps. What exactly you'd be left with neurochemically (and this would depend on your tolerance to amps) isn't obvious to me, but I suspect the physiological stress from the combo might even be milder than the 90 mg lisdex. alone, and it is unlikely to be a whole lot worse.

2) Google it. I suspect that your pulse wouldn't be a whole lot higher than from the lisdex. alone (and, if my suspicions above are correct, it might even be lower).

3) 50 mg of quetiapine isn't terribly high. I've known people who were on considerably higher doses medically during the day, and even higher for sleep. I've only heard of quet. being used recreationally in prisons, which would seem to suggest that most people don't use it recreationally when they have any other options.

Bioavailability isn't the only reason for insufflation; probably a more significant reason is to get it to the brain faster, which is a different issue than bioavail.

Hope this helps.

[ThusSpokeZarathustra]

For some reason swim was under the impression that after Vyvanse was metabolized (lisdex is a pro drug, and is converted to dextroamphetamine when taken orally (is this correct?)) it's effects were mostly in the d4 receptor. After a bit of research, swim concluded that Vyvanse's therapeutic affects on someone who actually has ADD, or ADHD were affected through the d4 receptor. When SWIM had read this initially, he gathered that the Vyvanse was active in the d4 receptor, and that seroquel has minimal to no effect on that receptor.

If anyone could correct this, or comfirm it, that'd be swell!

As for the bioavailbility factor, swim was kind of thinking that quetiapine might be less bioavailable intranasally than orally (like benzodiazepines), but if they're the same, then maybe Swim will try this next time (if there is one).

and thanks, Swim loves this forum because almost every response that he gets to a thread is helpful, or answers his question successfully.

ThusSpokeZarathustra added 7 Minutes and 41 Seconds later...

edit: swim is still unsure exactly the pharmacokinetic differences between Vyvanse and Adderall. It'd be awesome if someone could clear this up. From the source swim found initially (FDA's pharmacological review of Vyvanse), he gathered that 90 mg of Vyvanse was converted to only about > 30mg of dextroamphetamine (Adderall).

swim thinks he's misinterpreting something. It seems like it'd be higher than that.


ThusSpokeZarathustra added 25 Minutes and 10 Seconds later...

My apologies for the consecutive posts, but swim has pretty much come to the conclusion that the general consensus of the use of any atypical antipyschotic (i.e. Seroquel) in combination with amphetamines such as Vyvanse, Addrall, etc. hinders the amphetamines stimulant effect.

However, I found this interesting in that these atypical antipsychotic medications can also hinder dopamine induced amphetamine psychosis. Swim believes that he experienced a minor amphetamine psychosis about a week ago (he posted his issue), and it was rather unpleasant.

Therefore it might be in general interest of anyone that uses amphetamines, or cocaine excessively (or at least enough to produce psychosis), to keep a few Seroquel, or other pharmacologically related antipsychotics around to get rid of the all to eerie amph. psychosis. Though only because of these drug's minimal negative physiological synergy with amphetamines.

[Felix Guattari]

You are correct; lisdex is metabolized into d-amphetamine; lisdex. is just d-amphetamine with l-lysine glommed onto the N position. Amphetamine is released as lisdex. is hydrolyzed by the liver. The molecular weight of lisdex. is such that 25 mg vyvanse should be equal to 10 mg d-amp., but the bioavailability is somewhat higher due to the difference in pharmacokinetics - the area under the curve is equivalent, but the peak exposure is higher for lisdex..

Its hard to figure out what the exact dosage equivalencies would be for vyvanse vs. adderall, as you've got a lot of differing factors, but the official word from Shire is that, dosagewise, 70 mg vyvanse is equivalent to 30 mg adderall. Note, however, that this is likely going by several factors, and I don't know how they figured duration into the picture.

However, this still doesn't tell you anything about its equivalence to d-amp., as adderall is only 75% d-amp. (in 3 salts). If you go by their numbers (70 mg lisdex.=30 adderall; 3:1 ratio of d:l amps. in adderall), this should mean that 30 mg vyvanse=7.5 mg d-amp. This may not be quite correct, as the weight of the amp. salts in adderall varies, and I'm not sure if the usual 1:1:1:1 ratios take this into account. For the precise numbers you'll have to wait for someone with a longer attention span to crunch them for you.

Amphetamine itself acts on a variety of sites in the brain, but somewhat selectively. The primary effect of amp. is as a reuptake blocker, and so, by increasing intracellular levels, ends up nonselectively affecting all dopamine receptors. Quetiapine is (I believe) a selective antagonist, so the effects of amps end up being blocked incompletely.

SWiM's personal favourite antipsychotic for dealing with various amphetamine problems is olanzapine (Zyprexa). In SWiM's experience it doesn't so much abruptly end the effects of stims as let you down gently. For a kick, compare the molecular structure to that of quetiapine.

Hope some of that bunch of gibberish helped.

Reputation Comments on this post:

good information

[ThusSpokeZarathustra]

It does help, a lot. Thanks!

Swim wishes he would have thought of taking those Seroquel about this time tonight instead!! He never gets bad come down effects from Adderall or Vyvanse, but he does get very edgy and anxious. Like there's something important that swim forgot to do, and can't remember what it is, hah. An odd feeling, but nothing out of the ordinary for these kinds of drugs.

[Felix Guattari]

That's a sensation common for SWiM on comedowns from amps.