Brief Answer:
Avoid foods that cause contipation and take high fiber diet and laxative...

Detailed Answer:
Hi.
Thanks for your query, albeit short and specific.
Noted your umbilical hernia surgery just now, Wants to know the best foods to eat to avoid constipation from the pain medicines, Demerol and tramadol.

Frankly speaking you should continue taking the normal full diet or as advised by your Surgeon, unnecessary changes can create more problems.
If you are anticipating constipation, you may please take the medicines and see if these cause constipation in you or not as all the patients do not get constipation with these medicines.
If you had such an experience in the past, better to take laxative in consultation with your Doctor.
You can certainly avoid those foods and beverages which you might be knowing to cause constipation in you and to have high fiber diet.

I hope this answers your query.

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Brief Answer:
As noted below.

Detailed Answer:
Sure.
The best food composition to avoid constipation are:
Beans and Peas
Backed sweat potato
Broccoli
pitted plums (prunes) and prunes juice has very good laxative effect.
Whole grain bread.

Add berries, almonds and walnuts as per your taste.
In fruits pears. plums and apples have the best effects.
Flaxseed as per your taste.

Do not rush through. Go on increasing the quantities as per your past experience, which you must have observed to cause no other problems and at the same time helped you to relieve constipation.

And please remember to have adequate amount of water orally daily.

Also see that if you take the medicines like Demerol and Tramadol only when necessary, the dose may be drastically reduced and hence the constipation that is caused by them.
After a good, clean surgery, the need to have the painkillers is very minimal.

Wishing you all the best.

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