Is it possible that after taking Klabion I had no side effects, and after Klabax appeared?

Yes, it is possible that the equivalent of the drug Klabion caused side effects. By law, differences in the bioequivalence of substitutes can be up to 20%. As you can see, the generic drug may be slightly different from the original drug. The excipients contained in these equivalents should not have any therapeutic effect. In practice, however, it happens that they can be the cause of side effects. There is a risk that one of the "fillers" may, for example, irritate the gastric mucosa, which will cause inflammation and, consequently, cause a change in the absorption of the drug. Additives can also cause an allergic reaction. We wrote about it in detail here: https://www.gdziepolek.pl/artykuly/czym-sa-zamienniki-lekow Please remember that side effects of drugs should be reported to the doctor or individually. By reporting side effects, you help other patients, including your loved ones, who may also need the same medicine one day. This step also allows you to gather more information on the safety of medicinal products and update data on them. We wrote about how to do this here: https://www.gdziepolek.pl/artykuly/jak-i-dlaczego-zglaszac-dzialania-niepozadane