Bleeding gums: causes and what to do

Reviewed by Dr. Samar Fadavi, DDS

Short answer: Gums usually bleed because plaque along the gumline has caused inflammation called gingivitis. With careful brushing, daily cleaning between the teeth and a professional cleaning, mild bleeding often settles within one to two weeks. Bleeding that continues, or comes with swelling, loose teeth or bad breath, needs a dental exam.

Why do gums bleed when you brush or floss?

Seeing pink in the sink after brushing is one of the most common things people mention at a check-up. Many assume they brushed too hard, and sometimes that is part of it. Far more often, though, bleeding is the gum telling you it is inflamed. Healthy gum tissue is firm, pale pink and fits snugly around each tooth. Inflamed gum tissue is puffy, darker red and fragile, so it bleeds with very little pressure.

This guide explains the usual causes of bleeding gums, what you can do at home, what to avoid, and when bleeding is a sign that you should book a visit. It is general information for patients in Scarborough and East Toronto, not a diagnosis for your own mouth.

The most common causes

Plaque and gingivitis

Plaque is a soft, sticky film of bacteria that forms on teeth every day. When it sits along the gumline for more than a day or two, the body reacts to the bacteria with inflammation. That early stage is called gingivitis. Its classic signs are gums that bleed when you brush or floss, look red or swollen, and sometimes feel tender. The good news is that gingivitis is reversible. Once the plaque is removed consistently, the gum can return to health.

Tartar (calculus)

Plaque that is not removed hardens into tartar, also called calculus, within a few days. Tartar is rough and porous, so it holds even more bacteria, and a toothbrush cannot remove it. It tends to build up behind the lower front teeth and on the cheek side of the upper back teeth, close to where the salivary glands open. A professional cleaning removes it.

Gum disease that has moved below the gumline

If gingivitis continues for months or years, the inflammation can spread deeper and begin to damage the bone and fibres that hold the teeth. This is periodontitis. Bleeding may continue, but other signs appear too: gums pulling back from the teeth, pockets where food collects, bad breath that does not go away, teeth that feel loose or look as if they have moved. Periodontitis is not reversible in the way gingivitis is, but it can usually be controlled with treatment and good home care.

Brushing technique and a hard brush

A hard-bristled brush or a heavy scrubbing motion can scratch the gum and make it bleed, especially when the gum is already inflamed. A soft brush used with gentle, short strokes cleans just as well and is kinder to the tissue.

Starting to floss again

People often notice bleeding when they begin flossing after a long break. That bleeding comes from gums that were already inflamed between the teeth. If you keep cleaning gently every day, it usually eases within a week or two. Stopping because of the bleeding is the most common mistake.

Hormonal changes

Pregnancy, puberty and some stages of the menstrual cycle change how gum tissue responds to plaque. Many pregnant people notice their gums bleed more easily, a condition sometimes called pregnancy gingivitis. Keeping up with home care and a cleaning during pregnancy is safe and helpful. Tell us if you are pregnant when you book.

Medications

Blood thinners such as warfarin, apixaban and rivaroxaban, and daily low-dose aspirin, can make gums bleed more readily. Some medications for blood pressure, seizures and organ transplants can cause gum tissue to overgrow, which makes it harder to clean and more likely to bleed. Never stop a prescribed medication on your own because of gum bleeding. Bring a current medication list to your visit so we can plan around it.

Smoking and vaping

Smoking reduces blood flow to the gums. Because of that, smokers often bleed less even when gum disease is present, which can hide the problem. If you have recently quit, you may notice more bleeding for a while as circulation returns. That is a sign to keep up with cleanings, not a reason to worry.

General health conditions

Diabetes that is not well controlled makes gum inflammation more likely and harder to settle. Less commonly, bleeding gums can be linked to vitamin C or vitamin K deficiency, blood disorders or other medical conditions. If your gums bleed heavily, bleed without any brushing, or you also bruise easily or feel unwell, speak with your family doctor as well as your dentist.

What you can do at home, step by step

1. Switch to a soft toothbrush. Manual or powered, the bristles should be soft. Replace the brush or head every three months, or sooner if the bristles splay.
2. Angle the brush toward the gumline. Tilt the bristles about 45 degrees so they reach the place where tooth and gum meet. Use small, gentle circles or short strokes, two minutes, twice a day.
3. Clean between the teeth once a day. Use floss, floss picks, interdental brushes or a water flosser, whichever you will actually use. Curve floss into a C shape around each tooth and slide it just under the gum.
4. Use a fluoride toothpaste. Fluoride protects the teeth themselves while you work on the gums. Spit out the extra and avoid rinsing with water straight after.
5. Give it two weeks. Consistent gentle cleaning usually reduces bleeding noticeably in seven to fourteen days. Keep going even if it bleeds at first.
6. Consider an antibacterial rinse for a short period. A rinse can help, but it does not replace brushing and cleaning between the teeth. Ask us which type suits you, especially if you have a dry mouth.
7. Look at the bigger picture. Eat a varied diet with fruit and vegetables, drink water through the day, and if you smoke, ask your doctor about support to quit.

What to avoid

• Stopping flossing because of the bleeding. Bleeding between the teeth usually means those areas need more cleaning, not less.
• Scrubbing harder. More force does not remove more plaque. It wears the gum and the root surface instead.
• Relying on mouthwash alone. Rinses cannot reach under the gum or remove tartar.
• Ignoring bleeding that keeps coming back. Gum disease often develops quietly, without pain, until it is advanced.
• Stopping a blood thinner without medical advice. Speak with your doctor or pharmacist first, every time.
• Using sharp objects to pick at the gums. Toothpicks, pins or fingernails can cut the gum and push bacteria deeper.

How bleeding gums are checked at the clinic

At a dental exam, the dentist looks at the colour and shape of the gums, checks for tartar, and gently measures the small space between each tooth and the gum with a thin probe. Healthy spaces are shallow. Deeper pockets and bleeding when measured help show whether the problem is gingivitis or periodontitis. X-rays may be taken to look at the bone level around the teeth. You will be shown what was found and what the options are.

For gingivitis, a professional cleaning and a home care plan are usually enough. For periodontitis, a deeper cleaning below the gumline may be recommended, sometimes over more than one visit, followed by more frequent maintenance cleanings. If you have a medical condition or take medications that affect bleeding, the plan is adjusted to suit you. A routine visit is described on our check-ups and family dentistry page.

Bleeding gums at different stages of life

Children and teens

Children can get gingivitis too, often around new teeth, braces or areas that are hard to reach. Puberty can make gums more reactive. Supervising brushing until about age seven or eight, and teaching flossing early, helps. Our children’s dentistry page has more on young patients.

Adults with braces or aligners

Brackets and wires trap plaque. Interdental brushes and a water flosser make cleaning much easier. With clear aligners, brush before putting the trays back in so plaque is not sealed against the gums.

Older adults

Gum recession, dry mouth from medications, arthritis that makes brushing harder, and partial dentures that trap plaque can all make bleeding more likely later in life. A powered brush with a thicker handle, or help from a family member, can make a real difference. Our page on dental care for seniors explains how we adapt visits.

A simple two-week check for yourself

If you are not sure whether your gums are improving, try a short, honest check. For two weeks, brush twice a day with a soft brush angled at the gumline and clean between every tooth once a day. Each evening, note which areas bled and roughly how much. Many people find that the spots that bled on day one are quieter by day seven and almost settled by day fourteen. Areas that keep bleeding in the same place, even with careful cleaning, are worth pointing out at your exam. They often have tartar below the gum, an old filling edge that traps plaque, or a deeper pocket that needs attention. Bring your notes. They help the dentist focus on the right teeth and give you a clear picture of what home care can fix on its own and what needs help at the clinic.

When to see a dentist

Book an exam if any of the following apply:

• Your gums still bleed after two weeks of gentle, consistent cleaning.
• Your gums are swollen, shiny, very red or tender.
• Your gums look as if they are pulling back, or your teeth look longer.
• You have bad breath or a bad taste that does not go away.
• A tooth feels loose or your bite feels different.
• You see pus between a tooth and the gum.
• It has been more than a year since your last cleaning.

Call the same day if you have a swollen face, a painful lump on the gum, fever with gum pain, or bleeding that will not stop after firm pressure for 15 minutes. Those are reasons to be seen promptly, and our same-day emergency care page explains how to reach us. If you take a blood thinner and bleeding will not stop, contact your doctor or go to the nearest emergency department.

If you are covered by the Canadian Dental Care Plan, our CDCP page explains how cleanings and exams are handled at our office.

Questions about bleeding gums

Is it normal for gums to bleed a little when I floss?

It is common, but it is not a sign of healthy gums. Healthy gums do not usually bleed with gentle flossing. Light bleeding that stops within a week or two of daily flossing points to gingivitis that is settling.

Should I stop brushing the area that bleeds?

No. Keep brushing that area gently with a soft brush. Avoiding it lets plaque build up and makes the inflammation worse.

Can stress make my gums bleed?

Stress can lower the body’s resistance to infection and often changes routines such as sleep, diet and brushing. Both can make gum inflammation more likely.

Does a water flosser work as well as string floss?

For many people, especially those with braces, bridges or implants, a water flosser is a helpful option. The right choice is the one you will use every day. Ask us to show you what suits the spaces between your teeth.

Why do my gums bleed more during pregnancy?

Hormone changes make the gums react more strongly to plaque. Keep brushing and cleaning between your teeth, and a dental cleaning during pregnancy is safe. Tell us how far along you are when you book.

I take a blood thinner. Can I still have a cleaning?

Yes, in most cases. Let us know the medication and dose, and if your doctor has given you any instructions. We plan the visit around it.

Can bleeding gums affect the rest of my body?

Researchers have found links between gum disease and conditions such as diabetes and heart disease. Keeping your gums healthy is part of looking after your overall health. Our guide on oral health and overall health explains more.

How long until my gums stop bleeding?

With gingivitis, many people see a clear improvement within one to two weeks of careful home care, and more after a professional cleaning. If bleeding continues, the cause may be deeper and needs an exam.

Related guides

• Stages of gum disease explained
• Deep cleaning (scaling) explained
• Gum recession: causes and what helps