Yes, Desonide is indeed a mild steroid cream. I’d strongly suggest seeing a dermatologist to help you with a treatment regimen tailored for your needs.
Steroid creams should not be used long-term (more than 2 weeks at a time) because of possible side effects, including skin thinning. Some other options your doctor may recommend include topical/oral antibiotics (eg. metronidazole cream/gel or tetracycline), azelaic acid (Finacea), and beta-blockers.
I know what a pain constantly itchy skin can be – you might want to adopt preventative measures against known triggers as well, ie causes that could make your face red or flushed. Avoid hot drinks, spicy foods, caffeine, and alcoholic beverages. Avoid irritating cosmetics and facial products, and wear sun screen.