Tarceva and antacids - 1272881

You should not take any PPI's with Tarceva. This from the Tarceva site:
"•For drugs affecting gastric pH:
•Avoid concomitant use of Tarceva with proton pump inhibitors if possible. Separation of doses may not eliminate the interaction since proton pump inhibitors affect the pH of the upper GI tract for an extended period.
•If treatment with an H2-receptor antagonist is required, Tarceva must be taken 10 hours after the H2-receptor antagonist dosing and at least 2 hours before the next dose of the H2-receptor antagonist.
•Although the effect of antacids on erlotinib pharmacokinetics has not been evaluated, the antacid dose and the Tarceva dose should be separated by several hours, if an antacid is necessary."
Take care, Judy
http://www.tarceva.com/hcp/nsclc/dosing

Hi elizoc,

One medication which may help better than Tums would be ranitidine. As Dr. West has stated:

"The main information we have is that there is pretty consistent evidence that the EGFR inhibitors are not as well absorbed when the stomach is not a very acidic environment. Drugs like ranitidine or tums have a fairly transient effect on the stomach environment, so I tell my patients that if they do NEED to take antacids, they should take them at least a couple of hours after their EGFR inhibitor (tarceva these days in the US for the vast majority of patients). HOWEVER, the class of drugs called "proton pump inhibitors" (protonix, nexium, prilosec, prevacid) have a long-lasting effect and may be a problem to take at any time of day." - http://cancergrace.org/forums/index.php?topic=1569.msg9169#msg9169

In that same thread, our late friend and GRACE moderator Ned suggested investigating dietary influences on reflux:

"Maybe this could use some additional exploration. Shortly after I started Tarceva (October 2007) my heartburn/acid reflux, which had been mild on the previous chemo regimen, ramped up significantly. Ranitidine no longer did the job, and since I'd been advised against moving up to a proton pump inhibitor, I first cut out caffeine (which helped some) then decided to seriously pursue the food triggers angle with the help of our family physician. He said that among his patients, the two most common triggers were chocolate and tomatoes. I rarely ate chocolate, but tomatoes — either raw or in a tomato-based sauce — had been a big part of my diet without ill effect for many years. Nevertheless, after only two days without tomatoes my heartburn disappeared. For the remainder of the time I was on Tarceva (16 months) I avoided raw tomatoes, and if the family was having a dish containing a tomato sauce, I'd take just a little."

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"If it was too much, I'd know within an hour, and before long I became quite proficient in knowing how much I could eat without causing the reflux to set in.

Your dad's trigger may not be tomatoes, but there could be some food which, in combination with Tarceva, pushes things over the edge in a very predictable manner. When Tarceva eventually became ineffective against my cancer and I switched to a third-line chemo, the sensitivity to tomatoes disappeared within a few days and now I can eat anything I like. I guess that's my consolation prize!"

JimC
Forum moderator