Why Do I Bruise So Easily?

There’s a purple oval on your thigh the size of a plum. You have no memory of hitting anything. You think back through the week, the coffee table, the car door, the dog, and come up with nothing.

What a bruise is

Cleveland Clinic² calls a bruise, or ecchymosis, skin discoloration from damaged, leaking blood vessels under the skin. The blood pools without breaking through the surface. A bruise goes through color changes, starting red or purplish and fading through brown, green or yellow. Most fade within two weeks without treatment.

Why you bruise more easily

Cleveland Clinic³ lists five reasons.

Age. Your skin can become thinner as you age, which means less fat beneath it to cushion and protect your blood vessels.

Medicines and supplements. Even over-the-counter products can inhibit normal platelet function and cause bruising. Cleveland Clinic³ lists blood thinners, NSAIDs, SSRIs, and supplements such as fish oil and ginkgo. Harvard Health¹ adds corticosteroids like prednisone, which can make skin and blood vessels more fragile, and says aspirin and other drugs that interfere with clotting can make bruises larger and more noticeable.

Low vitamin levels. Cleveland Clinic³ names vitamin C, which strengthens blood vessels, vitamin K, which supports clotting, and vitamin B12, which helps make blood cells. Harvard Health¹ says nutritional deficiencies rarely cause bruising, though vitamin C deficiency (scurvy) can, and bruising can also come with zinc or B vitamin deficiency. So don’t start supplements on a guess. Our article on hair supplements explains why testing comes first.

Medical conditions. Cleveland Clinic³ lists von Willebrand disease, hemophilia, connective tissue diseases and low blood counts, which impair clotting or platelet function. Its bruise guide adds low platelet counts, and conditions such as cancer or liver disease.

Alcohol. Cleveland Clinic³ says heavy drinking interferes with liver and bone marrow function, which disrupts clotting.

If dry, fragile skin is part of the picture, see dry, itchy skin.

Caring for a bruise

Cleveland Clinic² describes rest and elevation, ice for the first 24 to 48 hours in sessions of no more than 15 minutes, then heat after two days, and over-the-counter pain medicine such as acetaminophen if you need it.

The play

Try this: a bruise log and a medicine list

Take a photo of any bruise with no clear cause, with a date.

Note where it is, and what you did that day.

Write a list of every medicine and supplement you take, with doses, including aspirin, ibuprofen, fish oil and anything you buy without a prescription. Bring both to your appointment.

When to get checked

Don’t wait if

1. Emergency

   If you have bleeding that doesn’t ease with firm pressure, or you hit your head and feel unwell, call 911.

Cleveland Clinic³ says to seek medical attention if a bruise doesn’t improve after a week, is unusually large or painful, keeps showing up in the same spot, appears without a clear reason, or shows up in places you’re unlikely to injure, like your back or torso. Its bruise guide adds bruises that last more than two weeks, frequent large bruises, painful swelling, and unusual bleeding. Harvard Health¹ says to contact your doctor about painful red spots on the legs.

Book an appointment if any of these fit:

• You’re bruising a lot more than you used to, with no explanation
• Bruises show up on your back, torso or in the same place repeatedly
• You also have unusual bleeding, such as nosebleeds or bleeding gums
• A bruise is unusually large, painful or swollen, or isn’t improving after a week
• You take a blood thinner, aspirin, a steroid or supplements and notice more bruising
• You drink heavily and are bruising

The plum on your thigh will fade through its colors. What it’s telling you is worth one phone call.