What options are best to treat my 20 month old daughter for psoriatic arthritis?

Depends:: Treatment involves rx for skin and joints: nonsteroidal anti-inflammatory medications; vitamins and minerals (to slow bone deformation); immunosuppressive meds; corticosteroids (for inflammation); light treatment (uvb or puva); heat and cold; splints; exercise; physical therapy; occupational therapy (to improve ability to perform activities of daily living); dermatology (skin) & surgery (joints).

Only peds rheumatolo: Psoriasis affect 2-4% of adults, psoriatic arthritis affect 30% of those a 20 month old child with psoriatic arthritis is very rare--arthritis in children are classified into multiple subcategories methotrexate the only commonly used-it slow destruction---enbrel, remicade, (infliximab) Humira has not had enough testing in children only a child rheumatologist can give you best guidance.