Gum pain is most often caused by the early stages of gum disease, but it can also come from canker sores, hormonal changes, an abscess, or even certain medications. Nearly half of adults over 30 have some form of gum disease, making it by far the most common explanation. The good news is that most causes of gum pain are treatable, and the most frequent one is fully reversible.
Gum Disease: The Most Likely Cause
Gum disease develops in two stages, and telling them apart matters because one can be reversed and the other can’t.
The first stage, gingivitis, is an inflammation of your gums that hasn’t yet damaged the bone or deeper tissue supporting your teeth. You’ll notice swelling, redness, soreness, and bleeding when you brush or floss. Some people also report a metallic taste or persistent bad breath. At this point, the damage is entirely reversible with better oral hygiene and professional cleaning.
If gingivitis goes untreated, it can progress to periodontitis, where the tissue and bone anchoring your teeth begin to break down. Gums pull away from teeth and form deeper pockets that trap more bacteria. Teeth may feel loose. About 42% of adults 30 and older have periodontitis, and roughly 8% have a severe form. Unlike gingivitis, the bone loss from periodontitis is permanent, though treatment can stop it from getting worse.
What’s Actually Happening in Your Gums
Bacteria in your mouth constantly form a sticky film called plaque on your teeth and along the gumline. When plaque isn’t removed, your immune system detects the bacterial toxins and launches an inflammatory response. Your gum cells release signaling molecules that increase blood flow to the area, causing the redness and swelling you see and the soreness you feel. If the bacteria stay put, they produce toxic byproducts that further ramp up inflammation, reduce your tissue’s ability to repair itself, and make your gums even more permeable to infection. This is why consistent brushing and flossing makes such a noticeable difference: removing the plaque shuts down the cycle before it escalates.
Canker Sores on the Gums
If your pain is focused on one spot rather than spread across your gumline, a canker sore (aphthous ulcer) may be the cause. These are small, oval sores with a red border that appear on soft tissue inside the mouth, including the gums. Minor canker sores heal on their own within one to two weeks without scarring. Major canker sores are deeper, larger, and can take up to six weeks to heal, sometimes leaving scars. Unlike gum disease, canker sores aren’t caused by bacteria and aren’t contagious. They’re often triggered by stress, minor injuries (like biting your cheek or irritation from braces), acidic foods, or nutritional deficiencies.
Hormonal Changes
Pregnancy is one of the most well-documented hormonal triggers for gum pain. Rising levels of progesterone and estrogen cause the tiny blood vessels in your gums to dilate and become more permeable. The result is gums that swell more easily, bleed more readily, and feel tender. This process typically begins around the second month of pregnancy and peaks around the eighth month, tracking closely with hormone levels. Progesterone also stimulates the production of prostaglandins, compounds that act as long-term drivers of inflammation in the tissue.
Gum tissue contains receptors for both estrogen and progesterone, which is why the gums respond so directly to hormonal shifts. The same mechanism can cause milder gum soreness during menstruation or puberty. In most cases, the inflammation subsides after hormone levels return to normal, but poor oral hygiene during these periods can allow it to progress into lasting damage.
Abscesses and Infections
A periodontal abscess is a pocket of pus that forms in the gum tissue, usually from a bacterial infection in a deep gum pocket or around a damaged tooth. It looks like a swollen bump or boil on the gum, often darker than the surrounding tissue. You may feel throbbing pain, sensitivity to hot and cold, pain while chewing, or a foul taste from draining pus. Some people notice a loose tooth near the affected area or swollen lymph nodes in the neck or jaw.
An abscess won’t resolve on its own and needs professional drainage and treatment. If you develop a fever, chills, nausea, difficulty breathing, or difficulty swallowing alongside gum pain, the infection may be spreading. That’s a situation requiring emergency care, not a wait-and-see approach.
Medications That Cause Gum Swelling
Certain medications can cause your gum tissue to overgrow, a condition called gingival hyperplasia. The swollen tissue presses against your teeth, traps food, and becomes painful and hard to keep clean. Three drug classes are the most common culprits:
- Anti-seizure medications, particularly phenytoin but also carbamazepine and valproic acid
- Calcium channel blockers used for high blood pressure, including nifedipine, amlodipine, and diltiazem
- Immunosuppressants, especially cyclosporine, which causes gum overgrowth in anywhere from 13% to 85% of people who take it
If you take any of these and notice your gums becoming puffy or painful, bring it up with your prescribing doctor. Switching to a different medication in the same class often resolves the problem, though it can take weeks for the tissue to return to normal.
Other Common Triggers
Not every case of gum pain points to disease or infection. Brushing too hard or using a stiff-bristled toothbrush can abrade gum tissue, causing soreness and recession over time. New orthodontic appliances, ill-fitting dentures, or a sharp edge on a broken tooth can all irritate the gums mechanically. Tobacco use, whether smoked or chewed, reduces blood flow to gum tissue and makes it more vulnerable to infection and slower to heal. Vitamin C deficiency, though rare in developed countries, directly weakens gum tissue and causes bleeding and pain.
Signs That Need Prompt Attention
Most gum pain improves within a week or two with consistent brushing, gentle flossing, and saltwater rinses. But certain signs indicate something more serious is going on. Swelling that keeps growing, pus or discharge from the gumline, bleeding that doesn’t stop after 10 minutes of pressure, a fever alongside dental pain, or pain that doesn’t respond to over-the-counter painkillers all warrant a dental visit sooner rather than later. A loose adult tooth is also a red flag, as it suggests the supporting bone has been compromised.
For gum pain that’s mild and recent, improving your brushing and flossing routine is a reasonable first step. If the soreness persists beyond two weeks or keeps coming back, a dental exam can identify whether you’re dealing with early gum disease, an abscess, or another underlying cause before it progresses.