Helicid is a safe drug and the risk of serious side effects after its use is negligible. Nausea, diarrhea or abdominal pain are most often observed. However, these ailments are temporary.
Metronidazole and Duomox are very commonly used drugs that have also been clinically tested and are considered safe. Please remember that any drug can cause side effects, but not everyone experiences them. Perhaps it is worth reading the content of our article:

https://www.gdziepolek.pl/artykuly/czy-bac-sie-dzialan-niepozadanych-lekow

Postponing therapy may be a much greater threat. Untreated infection may have serious health consequences, such as gastric or duodenal ulcers, and in extreme cases - stomach cancer.

I've attached links to helpful entries:

https://www.gdziepolek.pl/kategorie/leki-na-helicobacter-pylori

https://www.gdziepolek.pl/artykuly/jak-leczyc-wrzody-zoladka-i-dwunastnicy

Here you can check the availability of these medicines and make a reservation:

https://www.gdziepolek.pl/produkty/34578/helicid-20-kapsulki/apteki

https://www.gdziepolek.pl/produkty/48758/metronidazol-polpharma-tabletki/apteki

https://www.gdziepolek.pl/produkty/25590/duomox-tabletki/apteki