Patients have frequently described fatigue in association with chronic diseases, including cancer and a host of neurologic, metabolic, and psychiatric diseases. Fatigue can be influenced by factors such as the activity of the disease, medication, age, sex, and duration of symptoms. It presents a multidimensional influence with expression on physical, emotional, cognitive, and even social aspects of life. Fatigue also coexists and often interacts with other factors, including disturbance of mood, anemia, infections, fever, pain, sleep, and stress, making its evaluation complex. Psoriasis is a systemic inflammatory and chronic disease that can be widespread and recurrent. Patients with psoriatic arthritis have reduced physical activity (associated with pain, inflammation of joints, muscle hypotrophy, reduced muscular strength, and resistance), reduction of self-esteem, and depression and reduction of quality of life, leading to common somatic manifestations such as fatigue and sleep disturbances.