HCPCS Code J9299: Injection, Nivolumab, 1 mg

It can take up to an hour, not counting preparation and observation.

Besides the usual pain and discomfort in the injection site, it's possible for patients to feel nauseous and fatigued. They might also get skin rashes and itching, and even diarrhea. As for potential adverse effects that require immediate attention, these include inflammation of certain organs (e.g., lungs, liver, colon, endocrine glands) and other immune-related side effects.

This will depend on the patient's cancer and progression, but it'll take a few weeks to a few months before effects become noticeable.