What would cause someone to suddenly start bruising easily?

September 25, 2025 •

4 min read

According to the American Academy of Family Physicians, easy bruising can be attributed to a variety of factors, from lifestyle changes to underlying medical conditions. Understanding what would cause someone to suddenly start bruising easily is the first step toward finding a solution.

Quick Summary

Sudden easy bruising can stem from various factors, including new medications, nutritional deficiencies (like vitamin C or K), the natural thinning of skin due to aging, or an underlying medical condition such as a blood clotting disorder or liver disease. It's often a sign that small blood vessels are breaking more easily or that the blood's clotting ability is impaired.

Key Points

Medication Side Effects: Many common drugs, including blood thinners, NSAIDs, and corticosteroids, can thin the blood or weaken skin and capillaries, causing easy bruising.
Age-Related Skin Changes: As people get older, their skin thins and loses the protective fat layer and collagen, making blood vessels more fragile and prone to damage from minor bumps.
Underlying Medical Conditions: Conditions such as blood clotting disorders, liver disease, certain autoimmune diseases, and blood cancers can lead to an increased tendency to bruise easily.
Nutritional Deficiencies: A lack of essential vitamins, particularly vitamin C and K, can impair blood vessel health and clotting, contributing to unexplained bruising.
Seek Medical Advice for Sudden Changes: If you experience a sudden onset of large, unexplained, or frequent bruising, especially with other symptoms like fatigue or fever, it is important to see a doctor to rule out a serious underlying condition.
RICE Method for Bruises: For simple bruising from an injury, remember the RICE method: Rest, Ice, Compression, and Elevation, to reduce swelling and speed up healing.

Common Culprits Behind Sudden Easy Bruising

Bruising, or ecchymosis, occurs when small blood vessels (capillaries) near the skin's surface break from trauma, causing blood to leak into the surrounding tissue. While some people are naturally more prone to bruising, a sudden increase can be a sign of changes in your health. Understanding the potential causes is important for determining if and when you should seek medical advice.

The Impact of Medications and Supplements

Many medications and supplements can affect your body's ability to clot blood or make your skin more fragile, leading to easy bruising. It is crucial to never stop a prescribed medication without consulting a healthcare provider, but being aware of the potential side effects is key.

Blood Thinners (Anticoagulants): Drugs like warfarin (Jantoven), rivaroxaban (Xarelto), and apixaban (Eliquis) are designed to prevent blood clots. By their very nature, they also increase the likelihood of bleeding and bruising from even minor bumps.
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Regular or long-term use of over-the-counter pain relievers such as aspirin, ibuprofen (Advil, Motrin), and naproxen (Aleve) can interfere with blood clotting and contribute to easy bruising.
Corticosteroids: Both oral and topical steroids, like prednisone and hydrocortisone, can thin the skin and weaken capillaries, making them more susceptible to damage.
Certain Antibiotics and Antidepressants: Some of these medications may also affect blood clotting and increase bruising risk.
Herbal Supplements: Supplements like ginkgo biloba, fish oil, and vitamin E can have blood-thinning effects and should be discussed with a doctor, especially if you are on other medications.

The Role of Age and Skin Changes

As we age, our bodies undergo changes that can make bruising more common. This is a natural process, but it can still be concerning if the change is sudden.

Thinning Skin: The outer protective layer of skin, the epidermis, and the underlying fatty tissue that cushions blood vessels both become thinner over time. This offers less protection to the delicate capillaries, so they break more easily.
Collagen and Elastin Loss: The loss of these key proteins makes the skin more fragile and less resilient, contributing to easy bruising.
Sun Damage: A lifetime of sun exposure can weaken the walls of blood vessels, especially on areas like the forearms, leading to bruising.

Underlying Medical Conditions

While less common, a sudden onset of easy bruising can sometimes be a sign of a more serious underlying health issue. A healthcare professional can perform a physical exam and blood tests to rule out or diagnose these conditions.

Blood Disorders: Conditions affecting blood clotting can cause easy bruising. These include hemophilia, von Willebrand's disease, and platelet abnormalities like thrombocytopenia (low platelet count). Leukemia, a type of blood cancer, can also lead to easy bruising due to a low platelet count.
Liver Disease: Conditions such as cirrhosis can impair the liver's ability to produce the proteins necessary for blood clotting, leading to increased bruising.
Connective Tissue Disorders: Certain syndromes, like Ehlers-Danlos, cause abnormally fragile connective tissues, which can result in easy and extensive bruising.
Cushing's Syndrome: This condition results from an excess of the hormone cortisol and can cause the skin to become very thin and bruise easily.

Nutritional Deficiencies

Proper nutrition is vital for maintaining blood vessel health and normal clotting. A sudden dietary change or malabsorption issue can lead to deficiencies that increase bruising.

Vitamin C Deficiency: A severe lack of vitamin C, or scurvy, can weaken capillaries and connective tissue, making them prone to breakage and bruising.
Vitamin K Deficiency: This vitamin is essential for producing the proteins that help blood clot. A deficiency can lead to significant bleeding and bruising issues.

Comparison of Common Causes of Easy Bruising


Cause	Mechanism	Typical Onset	Related Symptoms	Risk Factors
Medications	Interfere with blood clotting or thin skin	Abrupt, after starting new medication	Other side effects of the drug	Usage of NSAIDs, anticoagulants, or steroids
Aging	Skin thinning and loss of protective fatty layer	Gradual over time, but can seem sudden	Fragile skin, sun damage	Older age, significant sun exposure
Blood Disorders	Impaired blood clotting or low platelet count	Can be sudden or gradual	Fatigue, fever, unexplained bleeding	Family history, cancer, liver disease
Liver Disease	Impaired production of clotting factors	Can be gradual; may seem sudden with advanced disease	Jaundice, fatigue, swelling	Excessive alcohol use, other liver conditions
Vitamin Deficiency	Impaired collagen or clotting factor production	Gradual, but may be noticed suddenly	Fatigue, joint pain, poor wound healing	Poor diet, malnutrition, absorption issues

When to Seek Medical Attention

While minor bruising is often nothing to worry about, certain signs should prompt a visit to your doctor to rule out a more serious condition. Consult a healthcare provider if:

Bruises are unusually large, painful, or develop frequently for no clear reason.
You have unexplained bruises on unusual areas, like your torso, back, or face.
Easy bruising is accompanied by other symptoms, such as fever, fatigue, unusual bleeding (like nosebleeds or bleeding gums), or jaundice.
You suddenly start bruising after beginning a new medication.
There is a known family history of easy bleeding or bruising.

Conclusion

A sudden increase in easy bruising can be caused by a wide range of factors, from benign lifestyle and aging changes to more serious underlying medical conditions. While many cases are harmless, it's always wise to pay attention to your body and consult with a healthcare provider if you notice significant, unexplained changes. Identifying the root cause is essential for determining the best course of action and ensuring your health and well-being. For more information on blood disorders and health, you can visit the National Heart, Lung, and Blood Institute website.

Frequently Asked Questions

Deficiencies in vitamin C and vitamin K are most commonly associated with easy bruising. Vitamin C is vital for producing collagen, which supports blood vessels, while vitamin K is essential for normal blood clotting.

While stress and fatigue don't directly cause bruising, they can sometimes be associated with underlying health issues that do, such as certain autoimmune disorders or poor nutritional habits. It's best to consult a doctor if bruising is accompanied by persistent fatigue.

If you notice increased bruising after starting a new medication, contact your healthcare provider. They can assess if it's a known side effect and determine if an adjustment to your dosage or medication is needed. Never stop taking a prescribed drug on your own.

Bruises that appear suddenly and without a clear cause, or are large and frequent, can sometimes indicate a more serious condition, such as a blood clotting disorder or liver issue. It warrants a medical evaluation, especially if accompanied by other symptoms like prolonged bleeding or fatigue.

Preventative measures include eating a balanced diet rich in vitamins C and K, taking precautions to avoid falls (especially for older adults), and discussing any new or existing medications with your doctor. Protecting your skin from excessive sun exposure can also help.

A normal bruise typically results from a known injury, is proportionate to the trauma, and fades within a couple of weeks. A more concerning bruise is often larger, appears without a known cause, occurs frequently, or is accompanied by other symptoms like fever or unexplained bleeding.

Yes, common over-the-counter pain relievers like aspirin and NSAIDs (ibuprofen, naproxen) can interfere with blood clotting, especially with regular use, and may cause you to bruise more easily.