Routinely test for eradication is not needed. In case you still want to go ahead, following is the protocol For confirmation of H. pylori eradication both the urea breath test and the biopsy based test (when endoscopy is clinically indicated) are recommended. Stool antigen test is also an accurate test although it seems to have a lower diagnostic value after eradication treatment. Testing should be performed at least of 4 weeks after treatment.

There is one stool antigen test but it's not required to get it done. Just continue medications prescribed by your doctor. Follow proper diet and that should be it.