Final answer:
Systemic steroids are not a common treatment for psoriasis due to the potential for a severe worsening of the disease upon withdrawal.
Step-by-step explanation:
The treatment for psoriasis that is NOT listed among the common options is systemic steroids.
While various topical and systemic treatments are indeed used for managing psoriasis, systemic steroids are generally avoided because they can cause a severe worsening of the disease upon withdrawal, known as a "rebound effect".
The other options provided, including topical steroids, steroid sparing agents such as dovonex and calcipotriene, UVA/UVB therapy, methotrexate, biologics like Enbrel and Humira, and oral agents like Otezla, are all appropriate treatments depending on the severity and type of psoriasis.