Bruising: when it is normal and when to contact us

Bruises are very common. Most are harmless and happen after a minor bump or knock, even if you do not remember injuring yourself.

What is a bruise?

A bruise happens when tiny blood vessels under the skin are damaged. A small amount of blood leaks into the surrounding tissue, causing a mark under the skin. Bruises may feel sore or tender for several days and can take around two weeks to fade.

Why do bruises change colour?

Bruises often start red or purple, then become blue, black, green, yellow or brown before fading. This colour change is part of the normal healing process as the body breaks down and clears away the leaked blood.

Why do I bruise more easily as I get older?

As we age, skin becomes thinner and loses some of the fatty layer that protects small blood vessels. This means even a minor knock can cause a noticeable bruise, especially on the hands, arms and legs. Sun-damaged skin can also bruise more easily.

Medicines that commonly make bruising more likely

Some medicines make bruising more likely because they affect blood clotting, platelet function or skin thickness. Do not stop prescribed medicines without speaking to a doctor, pharmacist or nurse.

Common examples include:

1. Warfarin
2. Apixaban
3. Rivaroxaban
4. Edoxaban
5. Dabigatran
6. Aspirin
7. Clopidogrel
8. Ticagrelor or prasugrel
9. Anti-inflammatory painkillers such as ibuprofen or naproxen
10. Steroids, including prednisolone tablets and long-term steroid creams or inhalers

Antidepressants, some cancer treatments and some supplements may also contribute to bruising in some people.

Why bruising is usually nothing to worry about

Bruising is usually not serious if it follows a bump or injury, is improving, and you otherwise feel well. Bruises can look dramatic, especially in older adults or people taking blood-thinning medication, but most settle without treatment.

You can help a new bruise by resting the area, raising it if possible, and applying a cold pack wrapped in a towel for 10–20 minutes. Do not put ice directly on the skin. Paracetamol can be used for pain if suitable for you.

When to contact the GP practice

Please contact us if you have:

• bruises that are increasing in number, size or frequency
• very large or painful bruises after only minor knocks
• bruising with frequent nosebleeds, bleeding gums, blood in urine or poo, or unusually heavy periods
• tiny red or purple pin-prick spots on the skin
• bruising WITH tiredness, weight loss, night sweats, recurrent infections, breathlessness or feeling generally unwell
• a personal or family history of bleeding problems
• new bruising after starting a new medicine
• a bruise that does not improve or is still worsening after two weeks

NICE advises that assessment of easy or unexplained bruising should include asking about trauma, medicines, bleeding symptoms, family history and possible signs of platelet or clotting disorders. Blood tests may be needed in some cases.

When to seek urgent help

Seek urgent medical advice today, via NHS 111 or urgent care, if you have bruising with significant bleeding, black stools, vomiting blood, severe headache after a head injury, confusion, collapse, severe abdominal pain, or a rapidly spreading purple rash.

Call 999 if someone is seriously unwell, has difficulty breathing, has collapsed, or has signs of a stroke or severe allergic reaction.

Important note about blood thinners

If you take warfarin, apixaban, rivaroxaban, edoxaban, dabigatran, aspirin or clopidogrel, bruising can be more common. However, these medicines are often prescribed to prevent serious conditions such as stroke, heart attack or blood clots. Please do not stop them without medical advice.