Visible Skin Discoloration
Your local Macy's or a similar store will have a line of cosemtics especially for camoflauging these kinds of things. The ladies at the counter can show you how to use them properly.
If it looks like a hickey, then it might be wise to cover it up. If it clearly looks like birthmark or something along those lines, it probably doesn't matter.
Tess
I had a sebaceous cyst on my neck that got infected and it looked like a hickey BUT I went to interviews with this scar. I could not afford plastic surgery and I promoted my skills, I didn't care what my interviewer thought about my scar. My scar is not the one working. It is my brain.
Now it is a joke. Everyone asks me if she showed me a good time! hahaha
Seriously, I can afford to take care of this scarring BUT I just do not have the time.
Well good for you. Confidence in oneself is always good. And one's ability to do the job is the most important thing. If you did run into an interview who stared or was turned-off, then that's his or her problem. People with tattoos also run into this and sometimes have to cover them up. Some say "Forget it. If they cannot accept me the way I am, then the heck with them." Others will cover it up to lessen the prospect that it even becomes an issue.
About the only time it becomes necessary is if you're consistently being rejected or stared at. In that case, corrective action becomes important to improving your chances of success.