Acid Dump, or why nighttime Delayed Release PPI dose should be given before 530PM
Dr. Phillips (creator of Zegerid and head of the former MARCI Kids) wrote this. Copying from a hard to find post on a BabyCenter forum.
SoluTab and any of the delayed release PPIs do not work at nighttime very well. Let me clarify, from 9 pm till about 2 am there is very little acid production (this is because of ancient genetic encoding). Ate the evening meal while day light 6pm or so, then go to sleep (then acid kicks in in early am (~2 am to 6 am) to kill any bacteria that were ingested). This remnant genetic predisposition is still with us. What do PPIs require to work??? (Answer: Actively secreting acid pumps). How long is the PPI in your babies system? (for approx 120 minutes after you give it). If the acid pumps (proton pumps) are not on during that time period then acid will not be blocked. Immediate release PPIs (such as Zegerid or BuferBabies/PPI) have a buffer in them and that turns on the acid pumps (in addition to protecting the PPI from acid degradation). So Immediate acting PPIs can be given without regard to meals (or even in the bottle)
Delayed release PPI such as Prevacid OTC need to have active acid secreting cells ("pumping") in order to block the pumps. The body shuts down pumps after 7 pm to ~3am. If you give the delayed release Prevacid, then it will be in the baby's body for 3.5 to 4 hrs after administration, then it will be gone. SO if you give the PPI after 5:30 it will have no effect because no pumps will be on while the Prevacid is in the bloodstream.
It is simple really, PPI drugs (such as SoluTab) can only block pumps that are in place and ready to make acid.
Well it is really quite interesting. The acid pumps are finite (meaning there are only so many available in a 24 hr period). When you use a buffer and immediate release PPI - the buffer hits the stomach and raises the pH. This makes the stomach lining send a signal to the acid secreting cells (parietal cells) to wake the pumps and get some of them making acid just a the PPI part hit the pumps and shuts them down. When you use a buffer, a lot of these pumps get used up. Therefore, by giving a dose around 8 or 9pm, or thereabouts, the pumps are exhausted and there aren't any to come on in the 2am period - so then there is no acid dump.
the SoluTab contains Prevacid in enteric-coated granules (inside the SoluTab). The medicine (lansoprazole) is absorbed in 1.5 hrs and the amt of time it is in the system is 120 minutes. So approx 3.5 hrs after a dose there is no drug in the system to block the acid pumps (called proton pumps). The nighttime acid begins at 2am and continues till 7 am (roughly). So, if you give a dose at 5:30pm then it is gone at 9pm (way before the acid pumps start making the nighttime acid).
Immediate release PPIs (such as Zegerid, BufferBabies, CaraCream) has a buffer that stimulates those pumps to come on (that would have come on from 2 am till ~7am) and then blocks them while they are on.