<s>[INST] My husband had a PET scan yesterday (his 3rd for stage 3a/b lung cancer). He has never had any kind of reaction before. The problem is the hand in which they injected him with the dye is swollen; his arm is too. Its getting hard as well as turning like a bluish/purplish color. It turns white when he pushes down on the arm. Also, it is causing him some discomfort and pain. Is this normal or should we get it checked? Since he hasnt had problems in the last year with the other PET scans, we are concerned. Please help, Im worried. Thank you! Sandra Hamilton br [/INST] Probably some amount of dye has been injected out of veins or there may be a small thrombophlebitis (infection of vein).rest, ice , limb elevation and analgesic such as ibuprofen will help you to relieve pain. If swelling increases or pain doesn't subsides and fever comes up within 24 hours, u Should consult to your treating doctor. Hope this answers your question. If you have additional questions or follow-up questions then please do not hesitate in writing to us. I will be happy to answer your questions. Wishing you good health. </s>