Brief Answer:
better to avoid Motrin (Ibuprofen) all together...

Detailed Answer:
Hello and welcome to 'Ask A Doctor' service...
I've gone through your query...
I can understand your concerns...

Well, it's better to avoid Motrin (i.e. Ibuprofen) all together after having gastritis...However, if it's acute gastritis, then better to avoid taking Motrin or any similar pain-killers for at least a period of 3-4 weeks or as directed by your treating physician...

If at all, there's any need to take pain killers, the safest one will be Acetaminophen (i.e. Tylenol), can be taken to a maximum of 4gm in a day, do ensure to drink a lot of water along with and always take after having some food...

-Additionally, please avoid smoking/alcohol strictly, if at all do, as they can further worsen this scenario...

-Avoid all form of fast/junk foods...no soda/carbonated drinks either...

Instead of two or three large meals, please try to have a small but frequent portion of meals, chew the food slowly, take your time and don't rush during eating...don't lie down immediately after having food, try to maintain a gap of 2-2.5hrs between dinner and bedtime...

Let me know if I can assist you further...

Wish you good health...

Take Care
Kind Regards

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