Combinations - lansoprazole (Prevacid) & lisdexamfetamine (Vyvanse)

[disturbedfuel15]

Hello everyone-
I've done much research on potentiating various drugs, but I cannot seem to find any information on the potentiating effects of "Prevacid" combined with "Vyvanse."
After seeing a psychotherapist, and finally a neurologist, SWIM was prescribed 50mg Vyvanse daily for adult ADHD. SWIM was as honest as possible with the psych, and told her about his marijuana use (rarely & on VERY special occasions), along with the other two daily prescription pills (non-narcotic) that he has been on from his previous doctor.
Unfortunately, SWIM forgot to mention that his old doc had put him on a three week trial pack of lansoprazole (Prevacid) for acid reflux/indigestion, which will become a prescription as soon as the trial packs are gone. The Prevacid is working very well for SWIM...
SWIM understands that Vyvanse is a relatively long-lasting Central Nervous System stimulant, which makes it hard to sleep many hours after taking it (no more naps). The problem is, the past three nights SWIM slept a grand total of four hours combined (approximately 1 or 2 hours a night). SWIM knows this is due to the CNS stimulant effects of the Vyvanse, and is going to try getting into a routine of waking up a few hours before work to take the Vyvanse at an earlier time (6am instead of 8:30am) so to help combat the sleeplessness he's experiencing. SWIM also understands that antacids can potentiate the effects of certain narcotic medications.
So, here's where SWIM's question comes in. Does anyone know if SWIM's daily dose of Prevacid could be potentiating the long-lasting stimulant effects of his Vyvanse? SWIM would love to talk to his psychologist about these symptoms, but unfortunately SWIM's psychologist is very busy and he cannot see her until his next appointment in a week and a half.
SWIM is not looking to abuse the drug; he's just trying to feel "normal." If SWIM feels Prevacid truly is potentiating the Vyvanse, he will ask his psych about alternative acid reflux/indigestion treatments. He doesn't want to switch to a different ADHD medication because he feels the Vyvanse really is working wonders for him and his condition.
Does anyone have any thoughts or ideas? SWIM would greatly appreciate any input on the matter.

Thanks!

P.S. Thanks for moving my thread, Benga.

[disturbedfuel15]

Well, since nobody knew the answer, SWIM decided to do a little experiment himself to find out if the Lisdexamfetamine was being potentiated by the Lansoprazole. SWIM did this by changing his body's intake of various substances along with the daily Lisdexamfetamine. Every day SWIM ingested the same type of food and the same amount/type of water/liquids during the same times. Here is what SWIM did during these experimental days:

Day 1) Took Lansoprazole and Lisdexamfetamine at the same time

Day 2) Took extra-strength Tums 45 minutes prior to dosage (this to further alkalize stomach acid). Proceeded to take Lansoprazole and Lisdexamfetamine concurrently.

Day 3) Took Lisdexamfetamine one hour prior to Lansoprazole

(SWIM tried to confine his experimentation to a three-day period to avoid false findings due to the tolerance issue with amphetamines.)

SWIM'S FINDINGS (for those interested):

Day 1) Lisdexamfetamine's effects started to kick in at T+00:30; full effects were noticed at T+01:10; full effects felt until T+08:00; after-effects felt until roughly T+13:00

Day 2) effects started to kick in at T+00:45; full effects were noticed at T+01:40; full effects felt until T+08:25; after-effects felt all the way into sleep at T+15:00

Day 3) effects started to kick in at T+00:25; full effects were noticed at T+00:55; full effects felt until T+08:00; after-effects felt until roughly T+13:00

CONCLUSION:

SWIM noticed no change in intensity the first two days, but a slightly faster onset (& ever-so slightly more intense feeling) on the third day. Antacids seemed to delay the absorption of the Lisdexamfetamine, but SWIM's findings show a negligible difference in amount of time the full-effects were felt...
In SWIM's opinion, when alkalizing agents are used concurrently (or prior to) Lisdexamfetamine, this produces no potentiating effects of the d-amphetamine itself, but does slow the absorption (& consequently the metabolism) of the Lisdexamfetamine as a whole. SWIM believes this is because the Lisdexamfetamine must implement the first-pass metabolism in order to hydrolyze and break down into l-lysine and d-amphetamine separately.

So, there it is. Let SWIM know what anyone else thinks of his findings. SWIM is very interested in other SWIMmer's opinions!

Reputation Comments on this post:

Well conducted study

[Lobsang]

The answer is that Prevacid would have no potentiation effect at all. It is a very cellular specific ATP-ase inhibitor. It is safe with all drugs as far as we know. And it would be extremely doubtful if it would act with any other medication. So no it did not potentiate the other drug.

[disturbedfuel15]

Just as SWIM's concluded through his experimentation. Like SWIM said, he believes antacids simply slow the absorption of the Lisdexamfetaime itself. Once the pill is absorbed, antacids have no effect on the metabolism or absorption of d-amphetamine or l-lysine alone.

Cheers guys-