Apple cider vinegar is effective in helping to clear up acne. You put a little bit on a cotton ball and put it onto the pimples. A little is worth a lot, but too much of it will irritate your skin and can make things worse. so don't oversoak the cotton ball.
But like everything else, if all you do is this it may not be completely effective. You must watch your diet as well. you should try for a diet low in fat and high in fiber along with avoiding peanut product, fried foods, excessive salt, dairy products, foods that are high in refined sugars, and high carbohydrate foods.
Why low fat? Because high fat consumption may elevate dihydrotestosterone levels, a form of testosterone. This specific hormone, when produced in excessive amounts by the body [and even in women], causes your oil glands to go into overdrive producing the natural oils that normally protect and moisturize the skin. This excess oil has nowhere else to go, and so it clogs the pores, resulting in blackheads, whiteheads, cystic acne, and smaller acne lesions because of the inflammation caused by the clogged pore.
Why salt and carbs? High salt intake can cause high iodine levels, and carbs increase insulin levels, both of which -- you guessed it -- increase dihydrotestosterone levels. Sugar obviously also raises insulin levels.
Oh, and one more thing -- as far as nurses and doctors and natural remedies, any *Good* physician would not have any problem with proven natural remedies that have a scientific basis. Nurses really don't have sufficient training to advise on these issues. If you run into any MD that does not know or understand the above information then you should change doctors, quickly.