Black patch growing on my fathers scalp. irregular border, large. he's remarked that his head hurts on the same side. photo: https://ibb.co/n1myn9r?

Sorry, but we cannot look at images at this site. It is very important that your dad sees a doctor to find out what this is. Only by getting seen by a doctor can his scalp get diagnosed and treated. He may need tests as well-like a biopsy-to determine the diagnosis. A dermatologist may be needed. Good luck!

For consults please use the paid Health Tap platform, you posted on the free platform. In general rapidly enlarging skin lesions have to be evaluated and treated timely.