Cuts that don’t involve much blood but might need stitches
The amount of blood visible is minimal, but there’s too much at risk to wait. If a cut is deep enough that it could involve tendons or nerves, which are just under the skin and hard to see, head to an ER immediately. Tendon injuries can take a while to start hurting, so you don’t want to leave it in case further damage occurs. And if you think something might be stuck in your wound—like glass—go now. While most minor lacerations will heal on their own and small objects usually stay put (they may even work themselves out), they could cause more damage if they move around while healing.
A skinned knee, say, or elbow. Even a small cut can turn into a big problem if it’s not properly cared for. The body is an amazing healing machine, but if you don’t let it work its magic, then you risk infection and further injury that may require surgery down the road.
Any cut where you can see bone (or nerves, tendons, or other internal organs). Cuts that won’t stop bleeding after 10 minutes of direct pressure with a clean towel. Cuts on your face. Any cut over an eye. Any deep cut over a joint, like a knee or elbow (even if it doesn’t hurt much). A puncture wound from an object like a nail, screwdriver, needle or toothpick. Cuts that are jagged and ragged and involve dirt or gravel. If any of these descriptions apply to your injury, seek emergency medical care instead of waiting for a primary-care appointment. It could save your life!