A swollen gum almost always signals inflammation, and the most common trigger is bacterial plaque building up along the gumline. But plaque isn’t the only explanation. Hormonal shifts, medications, nutritional gaps, and infections can all cause gum tissue to puff up, redden, or feel tender. Understanding the pattern of your swelling, whether it’s widespread or limited to one spot, helps narrow down what’s going on.
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 for too long, your immune system treats it as a threat. Cells in your gum tissue detect bacterial toxins and launch a defensive response, releasing signaling molecules that increase blood flow and fluid in the area. That’s the swelling you see and feel. The gums may also bleed when you brush or floss, and they often look redder than their usual pink.
Gingivitis is reversible. Consistent brushing, flossing, and professional cleanings can bring gums back to normal. Left alone, though, it can progress to periodontitis, a more serious condition where the gums start pulling away from the teeth and forming deep pockets. Bacteria colonize those pockets, causing further tissue damage and eventually bone loss. About 42% of U.S. adults over 30 have some form of periodontitis, so this progression is far from rare.
Swelling Around One Tooth: Abscesses
If the swelling is concentrated around a single tooth rather than spread across your gumline, an abscess may be the cause. There are two main types. A periodontal abscess forms in the gum tissue itself, usually in an existing pocket between the tooth and gum. A periapical abscess starts inside the tooth, at the root tip, typically from an untreated cavity or crack that lets bacteria reach the inner pulp.
Periapical abscesses tend to cause a severe, throbbing toothache that can radiate into your ear, neck, or jaw. You may notice sensitivity to hot and cold foods, bad breath, or a foul taste if the abscess ruptures and drains on its own. A periodontal abscess usually produces localized pain and a visible bump on the gum. Either type needs professional treatment. Antibiotics alone won’t resolve the underlying infection.
Hormonal Changes
Pregnancy is one of the most well-documented hormonal triggers for gum swelling. Rising progesterone levels cause the tiny blood vessels in gum tissue to widen, become more permeable, and leak more fluid into surrounding tissue. That’s a recipe for puffy, tender gums even with decent oral hygiene. Progesterone also suppresses parts of the local immune response while simultaneously creating a friendlier environment for certain anaerobic bacteria. One species in particular, Prevotella intermedia, thrives when progesterone and estrogen levels rise because these hormones can substitute for a growth factor the bacterium needs.
The result is that many pregnant people experience noticeable gum inflammation, sometimes called pregnancy gingivitis, even if they never had gum problems before. Puberty, menstruation, and menopause can produce similar (though usually milder) effects for the same basic reason: fluctuating sex hormones alter blood flow and bacterial balance in the mouth.
Medications That Cause Gum Overgrowth
Certain prescription drugs can make gum tissue physically enlarge, a condition called gingival hyperplasia. Three main drug classes are responsible. Anticonvulsants used for epilepsy and other neurological conditions are the most well-known culprits. Calcium channel blockers, commonly prescribed for high blood pressure, are another frequent cause, with nifedipine being the most strongly associated. The immunosuppressant cyclosporine, used after organ transplants and for some autoimmune conditions, rounds out the list.
Despite being pharmacologically very different, all three drug classes share this side effect. The overgrowth typically starts between the teeth and can eventually cover significant portions of the tooth surface. If you’ve recently started one of these medications and notice your gums getting thicker or more prominent, your dentist and prescribing doctor can discuss alternatives or management strategies.
Vitamin C Deficiency
Vitamin C plays a critical role in producing collagen, the structural protein that keeps your gum tissue and blood vessel walls strong. When your intake drops low enough, the small blood vessels in your gums weaken, leading to increased swelling, redness, and easy bleeding. This is one of the hallmark signs of scurvy, which is uncommon today but not unheard of, particularly in people with very restricted diets, certain digestive conditions, or heavy alcohol use. Even a moderate shortfall in vitamin C can worsen existing gum inflammation.
Other Common Triggers
Poorly fitting dental appliances, including dentures, braces, retainers, or night guards, can irritate gum tissue and cause localized swelling. A new crown or filling with a rough edge can do the same thing. Aggressive brushing with a hard-bristled toothbrush is another surprisingly common cause; it damages the delicate gum margin and triggers an inflammatory response that mimics early gum disease.
Smoking and tobacco use reduce blood flow to the gums, making them more vulnerable to infection and slower to heal. Diabetes impairs the body’s ability to fight bacterial infections, and people with poorly controlled blood sugar have significantly higher rates of periodontitis. Stress can also play a role by weakening immune defenses and encouraging habits like teeth grinding that put extra pressure on gum tissue.
What You Can Do at Home
A warm saltwater rinse is one of the simplest ways to calm inflamed gums. Mix about one teaspoon of salt into eight ounces of warm water, swish gently for 30 seconds, and spit. If your gums are very tender, start with half a teaspoon of salt instead. You can do this a few times a day, particularly after meals, but don’t overdo it since too much saltwater can be dehydrating.
Switch to a soft-bristled toothbrush if you aren’t using one already, and brush gently along the gumline at a 45-degree angle. Floss daily, even if your gums bleed at first. The bleeding usually decreases within a week or two as inflammation subsides. Antiseptic mouthwashes can help reduce bacterial load, but they’re a supplement to brushing and flossing, not a replacement.
If the swelling doesn’t improve within a week or two of consistent home care, a dental visit is the next step. Persistent swelling often means plaque has hardened into tarite below the gumline, which can only be removed professionally.
Signs That Need Immediate Attention
Most gum swelling is not an emergency, but a few warning signs change that calculation. A fever above 101°F alongside gum swelling suggests the infection may be spreading beyond the mouth. Difficulty swallowing or breathing, severe bleeding that won’t stop, or facial swelling that’s visibly progressing all warrant urgent care. These symptoms can indicate a deep tissue infection that needs treatment quickly to prevent serious complications.