Medicines for Subungual haematoma

What it is

A subungual haematoma is a collection of blood that becomes trapped under a fingernail or toenail, usually after an injury — such as trapping a finger in a door, dropping something on a toe, stubbing a toe, or repetitive pressure (for example from ill-fitting shoes during running, causing "runner's toe"). The trapped blood shows as a dark red, purple, brown or black discolouration under the nail, and, because the blood is under pressure in a confined space, it often causes throbbing pain, especially soon after the injury. Most subungual haematomas are not serious and heal on their own as the nail grows out, gradually moving up the nail. However, a significant injury can also involve a break in the bone beneath or damage to the nail bed, and a dark mark under a nail that appears without injury and does not grow out needs checking, as, rarely, it could be a sign of something more serious.

How it is treated

For a small, mildly painful subungual haematoma, treatment is usually just simple measures — resting and elevating the finger or toe, cooling the area, and pain relief — as it heals on its own with the trapped blood growing out with the nail over weeks to months. For a painful haematoma under pressure, a doctor can relieve the pressure and pain by making a tiny hole in the nail to release the trapped blood (a quick, effective procedure), which is done in the first day or two while the blood is still liquid. A significant injury may need assessment to check for a broken bone or nail bed damage, sometimes with an X-ray, and to decide on any treatment. The nail may sometimes come off as it heals, and usually regrows. Importantly, a dark mark under a nail that was not caused by an injury, or that does not move up and grow out over time, should be checked by a doctor to exclude other causes. The reassuring message is that most subungual haematomas from injury heal well.