Swollen gums are almost always a sign of inflammation, and the most common trigger is plaque buildup along the gumline. But several other factors, from hormonal shifts to medications to nutritional gaps, can cause your gums to puff up, turn red, or feel tender. Understanding the cause matters because it determines whether better brushing will fix the problem in a week or whether you need professional treatment.
Plaque Buildup and Early Gum Disease
The single most common reason for swollen gums is gingivitis, the earliest stage of gum disease. When plaque (a sticky film of bacteria) sits on your teeth near the gumline, it irritates the tissue and triggers an inflammatory response. Your gums swell, redden, and often bleed when you brush or floss. This is your body’s immune system reacting to bacterial buildup, not damage from your toothbrush.
The good news is that gingivitis is fully reversible. With consistent daily brushing and flossing, mild gum swelling typically improves within 3 to 7 days. Moderate inflammation can take 1 to 3 weeks to resolve. If the swelling doesn’t respond to better home care within that window, the problem may have progressed further.
Left untreated, gingivitis can advance to periodontitis, a more serious condition where the infection moves below the gumline and starts breaking down the bone that holds your teeth in place. Dentists check for this by measuring the pockets between your gums and teeth with a small probe. Healthy pockets measure 1 to 3 millimeters. Pockets deeper than 4 millimeters suggest gum disease has progressed beyond simple inflammation.
Hormonal Changes
Hormones play a surprisingly large role in gum health. Rising levels of estrogen and progesterone increase blood flow to your gums, making them more sensitive and more reactive to even small amounts of plaque. This explains why many women notice swollen or bleeding gums during pregnancy, menstruation, or puberty, even without any change in their oral hygiene routine.
The gums essentially overreact to bacteria that wouldn’t normally cause much trouble. During pregnancy, this is common enough that it has its own name: pregnancy gingivitis. The swelling usually resolves after hormone levels stabilize, but keeping up with brushing and flossing during these periods helps prevent the inflammation from worsening.
Medications That Cause Gum Overgrowth
Certain prescription medications can cause your gum tissue to actually grow and enlarge, a condition called gingival overgrowth. Three drug classes are most commonly responsible:
- Seizure medications, particularly phenytoin, though other anticonvulsants like valproic acid and carbamazepine have also been linked to the problem.
- Blood pressure medications in the calcium channel blocker family, especially nifedipine, amlodipine, and diltiazem.
- Immunosuppressants, particularly cyclosporine, which is used after organ transplants. Reported rates of gum overgrowth with this drug range from 13% to 85%.
If you started a new medication and noticed your gums swelling or growing over your teeth, that connection is worth raising with your prescribing doctor. Switching to a different medication in the same class can sometimes resolve the issue. Stopping a medication on your own is never the right move, but your doctor may have alternatives.
Vitamin C Deficiency
Vitamin C is essential for building and repairing connective tissue throughout your body, including your gums. When levels drop low enough, gums can become swollen, spongy, and purple, and they bleed easily. Severe deficiency is known as scurvy, which is rare in developed countries but not unheard of, particularly among people with very limited diets, certain eating disorders, or chronic alcoholism.
You don’t need to be in full scurvy territory for low vitamin C to affect your gums. Even a moderate shortfall can slow healing and make gum tissue more vulnerable to inflammation. If your diet is light on fruits and vegetables, this is a factor worth considering.
Diabetes and Blood Sugar
Poorly controlled diabetes creates a cycle that’s particularly hard on gums. High blood sugar raises glucose levels in your saliva, which feeds the harmful bacteria responsible for plaque. More plaque means more gum inflammation. At the same time, elevated blood sugar impairs your immune response, making it harder for your body to fight infections and slower to heal from them.
High blood glucose levels also increase the risk that mild gum disease will progress to severe periodontitis. If you have diabetes and notice persistent gum swelling, tighter blood sugar management is one of the most effective things you can do for your oral health, alongside regular dental visits.
Other Common Triggers
Beyond the major causes above, a few other things can make your gums swell. A piece of food lodged under the gumline (popcorn husks are a classic culprit) can cause localized swelling that clears up once the debris is removed. Ill-fitting dentures or orthodontic appliances can irritate gum tissue through friction. Tobacco use, whether smoked or chewed, reduces blood flow to the gums and makes them more prone to infection. Aggressive brushing with a hard-bristled toothbrush can also cause swelling, which is why soft-bristled brushes are recommended.
What Happens at a Dental Visit
If your swollen gums don’t improve with consistent home care, a dentist will examine your gums, measure pocket depths, and may take X-rays to check for bone loss. For gingivitis that hasn’t progressed, a professional cleaning is often enough to reset things.
For deeper infections, the standard treatment is scaling and root planing, essentially a deep cleaning done under local anesthesia. Your dentist or hygienist removes plaque and tartar both above and below the gumline, then smooths the tooth roots so gum tissue can reattach more easily. The procedure takes one to two hours and is nonsurgical. Antibiotics may be applied directly to the area or prescribed to take afterward. Ideally, you only need this done once. After the tartar and bacteria are cleared, regular cleanings and good brushing habits should keep your gums healthy going forward.
Signs That Need Prompt Attention
Most gum swelling is not an emergency, but certain symptoms warrant a dental visit sooner rather than later. Pus along the gumline, persistent bad breath that doesn’t improve with brushing, teeth that feel loose or have shifted position, or throbbing pain in a specific area all suggest the infection has advanced. Bleeding gums that remain tender and swollen after two weeks of consistent oral hygiene also deserve professional evaluation. Early detection is the biggest factor in keeping gum disease from causing permanent damage, including tooth loss.