When using medication, can I assume that urticaria of unknown origin, which appear sporadically several times a year, should be suppressed?

Clatra contains bilastin, which has an antihistamine effect, i.e. relieves the symptoms of diseases such as hay fever and can be used to treat itchy skin rashes (manifested m.in by urticaria). You are taking an increased dose because the standard dose in adults is 1 tablet (20 mg) per day. The second drug you use is probably Singulair, not "singularin". This drug contains montelukast, which inhibits the action of leukotrienes - compounds that cause narrowing and swelling of the respiratory tract, and are also responsible for allergy symptoms. Medications should be effective in the indication you mentioned (relieving skin symptoms or eliminating them). "Should" does not mean, however, that you can 100% guarantee effectiveness. I enclose additional information: https://www.gdziepolek.pl/artykuly/czy-alergie-mozna-wyleczyc