For a painful pimple on your neck, keep the area clean and avoid touching or squeezing it. Apply a warm compress a few times a day to reduce pain and swelling. If it gets bigger, very red, or develops pus, or if you develop a fever, see a doctor. Otherwise, it usually heals on its own in a few days.

Acnestar and Sotret do not contain the same ingredients and are not substitutes for each other. You should only switch when the ingredients and strengths are exactly the same, and preferably after checking with your doctor. The price difference between the substitutes is because different companies set their own manufacturing, marketing, and branding costs; the medicine works the same, but the brand name can make it cost more.