I live in the U.K. & suffered with psoriasis for 30 years. I have it on my arms, legs, back, bottom & hands.
Have tried so many creams, lotions & ointments over the years.
IMHO I find the only thing that makes it better is the sun.
Am under dermatologist who offered me a course of phototherapy which I declined as you can't go in the sun whilst having the treatment & I go to the beach a lot in the summer!
I always use high factor sun cream & find that just using hydramol ointment after a shower very beneficial.
When it flares up (usually if I'm stressed or injure myself) I use dovobet. I also have dovonex and betnovate. I have hydramol bath solution to which I soak in when my skin is very itchy.
There are so many different treatments out there & it depends on which type of psoriasis you have as to what works or not. I highly recommend seeing a specialist as they have so much more understanding than GP's.
Hope this helps