My 39 year old son has developed red bumps on the nape of his neck where the hairline is. we administered cortisone gel for the itching but to no ava?

There are a number: of infectious and parasitic disorders that could present with these findings. This will not be able to be evaluated over the internet. You need to see a health care provider (probably best to see a dermatologist) for appropriate evaluation and treatment.

Red bumps on Neck: With no response from cortisone - this can be a bacterial or fungal infection . You must seek an evaluation and treatment from a medical professional.