Does taking Dulsevia irregularly cause a headache?

I find no indication that duloxetine (the active ingredient in Dulsevia) can be used 'temporarily'. The drug is standard intended for regular, daily use. If you take the drug not as prescribed and unsystematically, it can not be ruled out that it contributes to the appearance of side effects. Regardless, headache is simply a very common side effect of Dulsevia - it may affect more than 1 in 10 people taking this medicine. If the headache is unacceptable, it's worth talking to your doctor about it. It should be mentioned, however, that you take the preparation irregularly: https://www.gdziepolek.pl/artykuly/jak-i-dlaczego-zglaszac-dzialania-niepozadane I enclose additional information about Dulsevia, the preparation can be booked online and collected stationary at the pharmacy upon presentation of a prescription: https://www.gdziepolek.pl/produkty/89259/dulsevia-kapsulki/apteki/w-warszawie