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Bleeding Gums: Common Causes and What to Do

Gums that bleed when you brush are often a sign of gingivitis, the early and reversible stage of gum disease. Here are the other common causes, what to do at home, and when to see a dentist or a doctor.

Updated September 2026·By the OHA editorial team·6 min read·How we write
Key takeaways
  • Bleeding when you brush is a common sign of gingivitis: plaque along the gumline irritating the gums. Treated early, it is usually reversible.
  • Keep brushing gently twice a day and clean between your teeth every day, even if your gums bleed. Stopping lets bacteria build up and makes the inflammation worse.
  • Brushing too hard, starting to floss, pregnancy and blood-thinning medicines can also make gums bleed.
  • See a dentist if your gums keep bleeding. See a doctor if bleeding gums come with easy bruising, nosebleeds, tiredness, fevers or frequent infections.

Gums that bleed when you brush are worth paying attention to. The Oral Health Foundation says gums bleed when they are irritated and inflamed, and that this is not considered normal. Often the cause is gingivitis (early gum disease), which can usually be reversed with good cleaning, but bleeding gums can occasionally be a sign of something else.

Why do gums bleed?

Gingivitis (early gum disease)

Gingivitis means inflammation of the gums. healthdirect Australia says it is caused by plaque (a sticky film of bacteria) building up on the teeth along the gumline, which irritates the gums and may make them bleed or swell. Bleeding when you brush is a common symptom; others are sore, red or swollen gums, bad breath or a bad taste, sensitive teeth, and receding gums (gums that move away from the teeth). healthdirect says about 1 in every 2 people will have gingivitis at some stage in their life.

If plaque is not cleaned off, the Oral Health Foundation says it can harden into tartar (also called calculus), which only a dentist or hygienist can remove. healthdirect says gingivitis treated early is usually reversible, because it does not damage the teeth or bone. Left untreated, it can develop into periodontitis, a more serious form of gum disease that can loosen teeth and may not be reversible. See gum disease.

healthdirect says people with a health condition such as diabetes or an immune disorder may be more likely to develop gingivitis.

Brushing too hard

The American Dental Association (ADA) says your gums could be bleeding because you brush too hard, and suggests an extra-soft or soft-bristled toothbrush. See how to brush your teeth.

Starting to floss

The ADA says that if you have just started flossing, your gums may bleed at first as they get used to cleaning between the teeth, and that this usually goes away on its own in about a week. See cleaning between your teeth.

Pregnancy

The ADA says some pregnant women develop pregnancy gingivitis, an inflammation of the gums that can cause swelling and tenderness, and the gums may bleed a little when brushing or flossing. See pregnancy and oral health. In England, the NHS says check-ups and treatment from an NHS dentist are free while you are pregnant and for 1 year after you give birth.

Blood-thinning medicines

The ADA says blood thinners may cause your gums to bleed, and to contact your doctor if the bleeding does not stop quickly. The NHS lists bleeding gums among the problems that can happen with anticoagulants (medicines that help prevent blood clots, sometimes called blood thinners) because you can bleed too easily. The NHS also says people taking warfarin should show their anticoagulant alert card to their dentist before any dental procedure.

Stopping smoking

The Oral Health Foundation says smoking can hide a gum problem because it restricts blood flow to the gums. If you have recently given up, better circulation to the gums may mean they start to bleed. See smoking, vaping and oral health.

Other mouth causes

healthdirect lists bleeding after dental treatment or surgery (such as having a tooth out), injuries to the mouth or teeth, mouth ulcers, mouth infections and mouth cancer.

Rarer medical causes

Occasionally, bleeding gums are part of a wider health problem, such as:

  • Leukaemia, a type of blood cancer. Cancer Research UK lists bleeding gums when you clean your teeth among the signs of bruising and bleeding easily, along with nosebleeds, very heavy periods and small dark red spots on the skin. healthdirect lists swollen, tender gums as a less common symptom. Cancer Research UK says most people with these symptoms do not have leukaemia, but it is important to get them checked by a GP.
  • Scurvy (severe lack of vitamin C). The NHS lists swollen, bleeding gums among its symptoms, but says scurvy is rare because most people get enough vitamin C from their diet. It says people at risk include those who have had no fresh fruit or vegetables for a while or eat very little.

What to do if your gums bleed

  1. Keep brushing. healthdirect and the Oral Health Foundation both say to keep brushing even if your gums bleed, because this gradually removes the plaque. Use a soft toothbrush and fluoride toothpaste twice a day (healthdirect).
  2. Be gentle. The Oral Health Foundation says you may need a softer brush while your gums are inflamed.
  3. Clean between your teeth every day with floss or interdental brushes. How often differs between sources: the NHS says every day and the ADA says floss once a day, while healthdirect's gingivitis page says to floss twice a day.
  4. Spit, do not rinse after brushing, and do not use mouthwash straight after brushing (NHS).
  5. Give it a few days. The Oral Health Foundation says that after a few days of thorough cleaning your gums should stop bleeding. If they do not, ask your dental team, as you may need a professional clean.
  6. Do not smoke (NHS).

If your mouth is bleeding after an injury or dental treatment, healthdirect suggests pressing on the area with gauze or a clean, slightly damp cloth for 30 minutes without checking, not rinsing your mouth, and seeing a dentist if it has not stopped.

When to see a dentist
  • Your gums bleed when you brush your teeth or eat hard foods, or are painful and swollen (NHS). The Australian Dental Association says your dentist will check the cause of the bleeding.
  • Your gums still bleed after a few days of thorough cleaning (Oral Health Foundation).
  • You have bad breath, or your child has sore, bleeding gums (NHS).
  • You have frequent or heavy bleeding in your mouth, a sore or ulcer that has not healed within 2 weeks, red or white patches, or signs of infection such as a fever of 38°C or higher: healthdirect says see a dentist or doctor.

When to see a doctor

The ADA says that if your gums bleed regularly or enough to worry you, you should see your dentist or doctor, because it could be a sign that something else is wrong. See a doctor (GP) if:

  • bleeding gums come with other signs of bleeding or bruising easily, such as nosebleeds or bruising more easily than usual, or with tiredness, fevers, weight loss or infections that keep coming back (Cancer Research UK)
  • you are taking a blood thinner and the bleeding does not stop quickly (ADA). The NHS says to call NHS 111 if you take warfarin and have symptoms of bleeding.
  • you are at risk of scurvy and have swollen, bleeding gums or bruise easily: the NHS says ask for an urgent GP appointment or get help from NHS 111
Get help urgently
  • Ask for an urgent dentist appointment if you have gum disease with very sore and swollen gums, teeth becoming loose or falling out, ulcers or red patches in your mouth, or a lump in your mouth or on your lip (NHS).
  • Heavy bleeding in the mouth needs urgent medical care because the airway could become blocked (healthdirect). In Australia, healthdirect says call triple zero (000) or go to the emergency department after a mouth injury if there is a lot of blood going down your throat, or you have trouble breathing, talking or swallowing.
  • The NHS says gum disease can lead to a dental abscess. That article lists the signs that need emergency care, such as swelling around your eye or neck.

Frequently asked questions

Should I stop brushing if my gums bleed?

No. healthdirect and the Oral Health Foundation both say to keep brushing gently, because leaving plaque on the teeth makes the inflammation worse.

Is it normal for gums to bleed when I start flossing?

It can happen. The ADA says gums may bleed at first as they get used to flossing and that this usually settles in about a week. If it does not, see a dentist.

Can bleeding gums be serious?

Usually they are a sign of gingivitis, which can be reversed. Left untreated, gum disease can progress and, rarely, bleeding gums are a sign of a medical condition. healthdirect says untreated gum disease can lead to periodontitis and abscesses, so it is worth getting checked.

Why did my gums start bleeding after I stopped smoking?

The Oral Health Foundation says smoking restricts blood flow to the gums and can hide gum problems. When you stop, better circulation can reveal them. Keep cleaning thoroughly, and ask your dental team if the bleeding has not stopped after a few days.

Sources

  1. Gum disease, NHS, accessed September 2026
  2. Anticoagulant medicines, NHS, accessed September 2026
  3. Warfarin, NHS, accessed September 2026
  4. Scurvy, NHS, accessed September 2026
  5. Gingivitis, healthdirect Australia, accessed September 2026
  6. Bleeding gums and dental bleeding, healthdirect Australia, accessed September 2026
  7. Dental injury, healthdirect Australia, accessed September 2026
  8. Leukaemia, healthdirect Australia, accessed September 2026
  9. Gum diseases, Australian Dental Association, accessed September 2026
  10. Bleeding gums, American Dental Association (MouthHealthy), accessed September 2026
  11. Why are my gums bleeding?, Oral Health Foundation, accessed September 2026
  12. Symptoms of leukaemia, Cancer Research UK, accessed September 2026

This article is general information about oral health. It is not a diagnosis or a substitute for advice from a dentist or doctor who knows your situation. If you have pain, swelling, bleeding that does not settle, or a problem that is getting worse, see a dental professional. In an emergency, contact your local emergency service.

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