Most bruises are harmless and heal on their own within about two weeks. But certain features, like unusual size, location, or bruises that appear without any injury you can recall, can signal something worth getting checked. Knowing what’s normal and what’s not can help you decide whether to wait it out or make an appointment.
How a Normal Bruise Heals
A typical bruise starts as a pinkish or red mark, then shifts to dark blue or purple over the first day or two. From there it fades through violet, green, and dark yellow before turning pale yellow and disappearing entirely. This full cycle takes roughly two weeks. If your bruise is following that color progression and gradually shrinking, it’s almost certainly healing normally.
The key word is “progress.” A bruise that stays the same dark color for days without any shift toward green or yellow isn’t behaving the way it should. That stalled healing is one of the clearest signs something else may be going on.
Warning Signs That Need Medical Attention
Not every bruise needs a doctor’s visit, but several specific red flags do. You should get a bruise evaluated if:
- It appeared without a known injury. A large bruise, or many smaller ones, showing up with no bump or fall to explain them is one of the most important warning signs.
- It’s large and appeared immediately after an injury. A bruise that balloons quickly and is very painful right after a hit or fall can indicate a sprain or broken bone underneath.
- It shows signs of infection. Red streaks spreading outward from the bruise, oozing, or a fever all suggest the area has become infected.
- It isn’t healing. If the bruise shows no signs of fading or changing color after a week or more, that’s abnormal.
- You’re bruising more easily or frequently than you used to. A pattern of increased bruising over time is worth investigating.
- The bruising started after a new medication. Some drugs affect clotting, and new bruising can be a side effect your doctor needs to know about.
Size and Location Matter
Bruise size gives doctors useful information. Clinicians generally consider bruises larger than one centimeter (a bit smaller than a dime) to be significant when they appear without any known trauma. If you’re developing bruises that size or larger and you can’t connect them to a bump or fall, that’s typically the threshold where a doctor will want to look deeper.
Location matters too. Bruises on your shins, forearms, and other bony areas that bump into things regularly are usually nothing to worry about. Bruises in less exposed places, like your torso, back, thighs, or face, are more concerning because those areas don’t get knocked around as easily in daily life. Unexplained bruising in these spots is more likely to reflect an internal problem rather than a forgotten bump.
When a Bruise Is Actually a Hematoma
A regular bruise is flat (or only mildly swollen), tender to the touch, and sits at skin level. A hematoma is different. It forms when a larger amount of blood pools and clots beneath the skin, creating a raised, firm lump that can be quite painful. It may look like a red, black, or blue bump rather than a flat discoloration.
Hematomas can also form deep in muscle tissue or near internal organs, where you can’t see them but can feel pain or pressure. A lump that’s hard, growing, or intensely painful after an injury is worth having a doctor examine, especially if it’s on your head, abdomen, or near a joint.
Medications That Increase Bruising
If you take any medication that affects blood clotting, easy bruising is a known side effect. Common culprits include aspirin, ibuprofen (Advil, Motrin), and naproxen (Aleve). Prescription blood thinners like warfarin and newer anticoagulants carry an even higher risk. Some antibiotics and antidepressants can also interfere with clotting.
Corticosteroids, often prescribed for inflammation or autoimmune conditions, thin the skin over time, making it easier for blood vessels to break and bruises to form. Even certain supplements can play a role: ginkgo biloba, for instance, has a mild blood-thinning effect that raises bruising risk.
If you notice increased bruising after starting any new medication or supplement, bring it up with your doctor. The fix may be as simple as adjusting a dose or switching to an alternative.
Health Conditions Linked to Easy Bruising
Unexplained or frequent bruising can sometimes point to an underlying condition. Vitamin K is essential for blood clotting, and a deficiency can lead to bruising and prolonged bleeding. Vitamin C plays a role in keeping blood vessel walls strong, so low levels can make vessels more fragile and bruise-prone.
More serious possibilities include platelet disorders, where your blood doesn’t have enough of the cells responsible for clotting, or conditions affecting the clotting process itself. Inherited bleeding disorders like von Willebrand disease cause people to bruise easily throughout their lives, though some cases are mild enough that they go undiagnosed until adulthood. In rare cases, unexplained bruising can be an early sign of blood cancers like leukemia, which disrupts normal blood cell production.
These conditions are uncommon, and easy bruising alone doesn’t mean you have one. But when bruising is paired with other symptoms, like nosebleeds, bleeding gums, heavy periods, or fatigue, it strengthens the case for testing.
What to Expect at the Doctor’s Office
If your doctor wants to investigate your bruising, the process typically starts with blood work. A complete blood count checks whether you have enough platelets and healthy blood cells. Clotting time tests measure how quickly your blood forms clots through different pathways. Your doctor may also check a blood smear, which lets a lab technician look at your blood cells under a microscope for abnormalities.
If those initial tests come back normal but you’re still bruising significantly, you may be referred to a hematologist, a specialist in blood disorders, for more detailed evaluation. The testing itself is straightforward: a blood draw and sometimes a physical exam of your bruises, their size, and their distribution.
How to Treat a Bruise at Home
For a normal bruise that doesn’t raise any red flags, you can speed healing and reduce discomfort with the RICE approach: rest, ice, compression, and elevation. Rest the area for the first day or two, avoiding activities that put stress on it. Apply ice through a cloth or towel for 10 to 20 minutes at a time, repeating every hour or two during the first day. This helps limit bleeding under the skin and reduces pain.
If the bruise is on a limb, wrapping it gently with a compression bandage can help control swelling. Keep it snug but not tight enough to cause numbness or tingling. Elevating the bruised area above heart level when you’re resting slows blood flow to the site and encourages drainage, which reduces both swelling and discoloration. After the first couple of days, gradually return to normal movement as pain allows.