My son (18) has some swelling and white discharge from one nipple. no pain. should i take him to urgent care or wait fro a routine appointment?

Interesting: If the white discharge is pus, and there is a lot of redness and tenderness to the area, then he may have an infection. Urgenbt care would be appropriate. However, this may be galactorrhea, which is very unusual in a male and may be a sign of endocrine dysfunction. That is less urgent, and can probably wait for an appointment with his primary care physician.