My husband was diagnosed with copd by xray. should he get additional diagnostics as he is lethargic and has lost weight.?

Need to see Doc: Yes, he should his doc or a lung specialist, lethargy and weight loss is concerning. I do not know if a cat scan of the chest is necessary to exclude any lung mass. Lethargy can result if he is retaining carbon dioxide because of severe copd. Work up is needing for his copd, weight loss and lethargy including lung function tests.

Consider ER...: He needs an arterial blood gas to determine his oxygen and carbon dioxide levels as he may need supplemental oxygen if his level is low or even artificial ventilation if his carbon dioxide level is high. He needs pulmonary function testing, once stabilized, to verify the diagnosis and determine severity. He may need a ct scan of his chest. To rule out respiratory failure, go to the er asap!

Yes: Yes, definitely. He needs pulmonary function tests and perhaps a ct scan to make sure he doesn't have cancer as well. Good luck!