I have been blessed with clear skin all my life, but lately I have been getting large pimples — I think it’s “cystic acne” — on my back. I’m 50 years old and have no experience with this. It takes weeks for them to go away and they leave a little scar. What’s going on here?

A combination of things is happening involving diet, exercise, hormones, and stress. Address your diet and make sure you don’t eat sugar substitutes, soda, dairy, and fried foods.

Make sure after you exercise you take a shower and don’t let the sweat dry on your body. At 50, you are perimenopausal, most likely, meaning your hormone balance isn’t the same as it was in your 30s.

You may want to consider progesterone or estradiol for part of the month and make sure your testosterone levels are not high.

Take a course of doxycycline prescribed by your doctor and see if things improve. Finally, take a milk thistle supplement for a month to cleanse and detoxify your liver. If often helps.