Is numbness of the right part of the lower abdomen and thigh after several days of using Furagina a cause for concern?

Thank you for sharing your case. According to the Summary of Product Characteristics, nervous system dysfunction (tingling, numbness, sensation of running currents) is a common side effect of Furagina. I encourage you to report an adverse reaction if you have not already done so: https://www.gdziepolek.pl/artykuly/jak-i-dlaczego-zglaszac-dzialania-niepozadane If you notice these symptoms yourself, you should stop taking Furaginum and see a doctor who will adjust the further treatment according to your current clinical condition. If you are unable to get to your primary care doctor, the gdziepolek.pl Service also allows you to obtain a teleconsultation with a doctor: https://www.gdziepolek.pl/telekonsultacja