Psoriasis is a long-term inflammatory disease and the treatment needs to be continued till the disease is present. Over time; after many years disease activity can self-subside but till it is present the treatment needs to be continued regularly. Also the choice of treatment depends upon the extent of involvement. Treatment involves lotions and creams for localised involvement. However, in widespread involvement there is need for systemic immunosuppressants. Also, whether is there accompanying joint problem as well will guide the choice of treatment . You should send me images through private online consult for a better assessment of the problem and approaching it accordingly. Hope this is helpful.