Moles, also known as nevi, are common skin growths that appear as small, often pigmented spots. They form when melanocytes, the cells responsible for producing skin pigment, grow in clusters instead of being evenly distributed. Most adults typically have between 10 and 40 moles on their body, and while they are generally harmless, it is natural to wonder what happens if one is irritated or scratched.
What Happens Immediately and How to Respond
If a mole is scratched, it can result in minor bleeding, irritation, or mild pain. This occurs because moles, like the surrounding skin, contain small blood vessels that can be injured if injured. Injury severity depends on the scratch’s force.
If you scratch a mole, follow basic first aid to prevent complications. Begin by gently cleaning the area with mild soap and warm water to reduce the risk of infection. If the mole is bleeding, apply gentle, direct pressure with a clean cloth or sterile gauze until the bleeding stops. You may then apply an over-the-counter antiseptic ointment to the wound and cover it with a clean bandage to protect it from further irritation and contamination.
The injured mole will heal like any other minor skin wound, often forming a scab. Most injuries resolve within three to five days. However, an open wound on the skin, including a scratched mole, carries a risk of infection if bacteria enter the area. Signs of a potential infection include persistent redness, swelling, increased pain, or the presence of pus or other discharge that may be yellowish, greenish, or have a foul odor. A fever or red streaks extending from the wound are also indicators that medical attention may be necessary.
Scratching Moles and Cancer Concerns
Many worry if scratching a mole can cause cancer. Physical trauma, like scratching, does not cause melanoma or other forms of skin cancer. Skin cancers, including melanoma, develop due to genetic mutations within melanocytes, the pigment-producing cells, rather than from external injury. In fact, only a minority of melanomas, about 20% to 30%, originate from existing moles; most appear on previously unaffected skin.
While scratching does not induce cancer, it can sometimes draw attention to a mole that may already have suspicious characteristics. Alternatively, it might simply cause a benign mole to bleed, leading to unnecessary worry. It is also worth noting that repeatedly irritating a mole could potentially make it more challenging for a healthcare professional to assess it accurately in the future, particularly if its shape or texture is altered by the injury.
Instead of focusing on scratching as a cancer cause, be aware of signs that warrant concern. These signs are often remembered using the ABCDE rule:
- Asymmetry: One half of the mole does not match the other.
- Border irregularity: Edges are ragged, notched, or blurred.
- Color variation: Uneven color or multiple shades of brown, black, or even red, white, or blue.
- Diameter: Larger than 6 millimeters, roughly the size of a pencil eraser.
- Evolution: Any change in the mole’s size, shape, color, or elevation, or any new symptoms like bleeding, itching, or crusting.
If a mole continues to bleed without cause, does not heal within a few days after being scratched, or exhibits any of these ABCDE changes, it is advisable to seek evaluation from a medical professional.