Very good shampoo that my doctor recommended to me. She told me to use it every third wash because it is heavy. And I saw a difference over time. (Leave it on the head for 3-4 minutes)

Last update: I changed shampoo and started using a supermarket brand (non-pharmaceutical) that is simply for oily hair. I saw better results. I can now confidently say that this specific product is not worth even half a euro.
1.5 months later: no improvement in oiliness, no difference compared to regular shampoo, wasted money!!
The dermatologist told me to buy it to regulate the oiliness on my scalp and to wash my hair less frequently. So far, after three uses, I can say that my hair gets oily a little earlier than before!

It has a subtle scent and cleans deeply, leaving the hair lightweight and easy to comb. Unfortunately, it doesn't deliver on its promises as the hair becomes oily after a few hours.