Case on psoriasis -

A 28 yrs of male patient  is presented with itching and rashes. The rashes started from the belly and gradually migrated towards the extremities.His skin appears to be red and erythematous and has become dried and crusty in some regions due to itching and scratching.

Pt gives history of smoking and consuming drugs since 12 years.

Dx: psoriasis.

Suggest  a suitable treatment plan.