Why Is My Bruise Getting Bigger and Spreading?

October 1, 2025 •

4 min read

It's a common observation for many that a bruise doesn't stay in one place, but actually appears to expand or migrate across the body over time. A bruise can get bigger and spread for both benign and concerning reasons, from simple gravity to more complex medical issues. Understanding the difference is key to knowing when to seek medical advice.

Quick Summary

Bruises can appear to grow and spread due to gravitational forces pulling pooled blood deeper into surrounding tissue. While often a normal part of the healing process, a rapidly enlarging bruise with severe pain or swelling, or one that occurs without known injury, could signify a more serious condition like a hematoma or internal bleeding. Age, medications, and underlying medical issues like bleeding disorders or vitamin deficiencies can also cause a bruise to get bigger and spread.

Key Points

Normal Migration: Bruises can appear to spread due to gravity pulling pooled blood downwards, a normal part of the healing process.
Hematoma Formation: A rapidly enlarging, swollen, and painful bruise could be a hematoma, a more serious pooling of blood that may require medical attention.
Underlying Conditions: Frequent or unexplained bruising can be a sign of underlying issues, including bleeding disorders, liver disease, or certain cancers.
Medication Effects: Medications such as blood thinners and NSAIDs can increase bruising. Consult a doctor if you notice new bruising patterns.
When to See a Doctor: Seek prompt medical care for bruises with severe pain, rapid enlargement, or accompanying symptoms like fever, numbness, or bleeding from other areas.

Understanding the Bruising Process

A bruise, medically known as a contusion, occurs when tiny blood vessels, or capillaries, rupture beneath the skin's surface, causing blood to leak into the surrounding tissue. This pooled blood is what causes the characteristic discoloration. The process of a bruise getting bigger and spreading is often tied to the body's natural response and the forces acting upon the pooled blood.

The Role of Gravity

One of the most common and harmless reasons for a bruise to spread is gravity. After an injury, blood pools in the area of impact. Over the following days, this blood, along with other fluids, can travel downward due to gravity, making the bruise appear to migrate and enlarge. For example, an injury on the knee might result in a bruise that later appears around the shin or ankle. This is a normal part of the healing process as the body works to reabsorb the collected blood.

Hematomas vs. Simple Bruises

Another reason for a growing area of discoloration and swelling is the presence of a hematoma. While bruises and hematomas are often confused, they are different conditions. A hematoma is a larger, more severe collection of blood outside the blood vessels, forming a swollen lump under the skin. A bruise (contusion) results from damage to smaller capillaries, but a hematoma involves bleeding from larger blood vessels and can be deeper within the tissue. While a bruise typically resolves in a week or two, a hematoma can last for months and may require medical intervention, especially if it's large or puts pressure on surrounding nerves.

Comparison Table: Bruise vs. Hematoma


Feature	Bruise (Contusion)	Hematoma
Cause	Damage to small capillaries	Damage to larger blood vessels
Appearance	Flat, discolored area	Raised, swollen, painful lump
Feeling	Tender to the touch	Firm or spongy, very tender or painful
Size	Generally smaller	Larger, can cause significant swelling
Healing Time	1-3 weeks	Weeks to months, depending on size and location
Potential Severity	Rarely serious	Can be serious, especially if large or internal

Medical Conditions and Other Factors

Sometimes, a spreading or unusually large bruise can be a symptom of an underlying medical condition. If you experience frequent, large, or unexplained bruising, it is important to consult a healthcare provider.

Conditions that can cause excessive bruising include:

Bleeding disorders: Conditions like hemophilia and Von Willebrand disease affect the body's ability to clot blood, leading to easy and excessive bruising.
Liver disease: A compromised liver produces fewer of the proteins needed for blood clotting, resulting in frequent bruising.
Low platelet count (Thrombocytopenia): A reduced number of platelets, which are essential for clotting, can lead to widespread bruising, sometimes appearing as tiny red or purple dots called petechiae.
Leukemia: In rare cases, leukemia can cause excessive bruising due to abnormal blood cell production in the bone marrow.
Certain medications: Blood-thinning medications (anticoagulants), aspirin, NSAIDs (like ibuprofen), and corticosteroids can increase bruising. If you notice new bruising patterns after starting a medication, speak with your doctor.
Aging: As we get older, our skin becomes thinner and loses its protective fatty layer, while blood vessels become more fragile. This makes older adults more susceptible to bruising from even minor bumps, a condition known as senile purpura.

When to Seek Medical Attention

Most bruises are harmless and will heal with time, but certain symptoms warrant a visit to a healthcare professional immediately.

You should seek medical help if:

The bruise is accompanied by severe swelling or pain.
You notice numbness, weakness, or increased pressure in the affected limb.
The bruise seems to be rapidly growing or spreading.
A firm lump (hematoma) forms under the bruise.
You have bruising for no obvious reason, or it occurs in unusual places like the head, trunk, or back.
You experience unusual bleeding elsewhere, such as from the gums or nose.
The bruise doesn't show signs of fading after two weeks.

For more information on serious symptoms, see the Mayo Clinic first aid guide for bruises.

Home Treatment for Minor Bruises

For most minor bruises, the R.I.C.E. method can help manage symptoms and aid healing.

R.I.C.E. Method:

Rest: Rest the injured area to prevent further damage. Avoid strenuous activity involving the bruised body part for the first few days.
Ice: Apply a cold compress or ice pack (wrapped in a towel) to the area for 15-20 minutes, several times a day, during the first 48 hours. This helps constrict blood vessels and reduce swelling.
Compression: Gently wrap the bruised area with an elastic bandage to provide support and help control swelling. Ensure it is not wrapped too tightly.
Elevation: If possible, elevate the bruised limb above the level of your heart. This uses gravity to help drain fluid away from the injury and minimize swelling.

After 48 hours, some people find applying heat can help increase blood flow to the area and promote the reabsorption of blood.

Conclusion

In many cases, a bruise getting bigger and spreading is a normal and harmless consequence of gravity acting on pooled blood during the healing process. However, significant and rapid spreading, accompanied by severe pain, excessive swelling, or a palpable lump, should be evaluated by a healthcare professional to rule out a hematoma or more serious underlying issues. Furthermore, unexplained or persistent bruising, especially if it appears frequently or in unusual locations, warrants medical attention. While home remedies like the R.I.C.E. method can effectively manage minor bruises, being aware of the warning signs is crucial for your health and well-being.

Frequently Asked Questions

Yes, it is often normal for a bruise to appear bigger or to spread in the first few days after an injury. This is primarily due to gravity pulling the blood and fluids deeper into the surrounding tissue as your body begins the healing process.

A bruise, or contusion, involves minor bleeding from small capillaries under the skin, resulting in discoloration. A hematoma is a more significant, localized collection or pool of blood from larger blood vessels, often forming a raised, painful lump.

You should be concerned about a spreading bruise if it grows rapidly, is accompanied by severe pain, significant swelling, fever, or occurs without any known injury. A palpable lump under the bruise is also a sign to seek medical attention.

Yes, several medications can affect blood clotting and increase the risk of bruising. These include blood thinners (anticoagulants), aspirin, NSAIDs (like ibuprofen), and corticosteroids. Discuss any new or unusual bruising with your doctor if you are on medication.

If a bruise on your thigh or knee spreads downward towards your lower leg or ankle, it is often a normal effect of gravity and not usually a cause for alarm. Continue with home care like elevation and cold packs, but monitor for signs of a hematoma or infection.

Conditions that cause easy or unexplained bruising can include bleeding disorders like hemophilia, liver disease, certain blood cancers such as leukemia, low platelet count, and vitamin deficiencies (C or K).

For a large and painful bruise, follow the R.I.C.E. protocol immediately after the injury: Rest the area, apply Ice (wrapped in a towel) for 15-20 minutes at a time, use Compression with an elastic bandage, and Elevate the affected limb above heart level to reduce swelling.