Apple cider vinegar contains acetic acid, a substance that can help fight infections and bacteria, thanks to its antibacterial and antiseptic properties. However, it is important to remember that it is still an acid. So if you have sensitive skin or a wound, it may cause irritation. In this case, we recommend that you opt for another treatment. How it works: First, soak the cotton wool in apple cider vinegar. Next, attach it to the bump behind the ear with the bandage or espadrille and leave it on for a while. Remove the bandage after the specified time. You should find that a scab has formed which will fall off by itself in a few days. If not, repeat the procedure for as many days as necessary, but always pay attention to the condition of your skin to avoid irritation. When the scab falls off, wash the area with mild soap or antiseptic. Then apply another dressing, but without apple cider vinegar. A few days later, the infection and lump should be gone.