Mouth Pain in Children: Causes, Symptoms & Treatment

What Are the Symptoms of Mouth Pain in Children?

The main symptoms of mouth pain in children include refusing to eat or drink, increased drooling, irritability, and sometimes mild fever. Older children (over age 2) can usually verbalize that their mouth hurts, while infants show distress through behavior changes and excessive drooling.

Recognizing mouth pain in young children can be challenging, especially in infants and toddlers who cannot yet express what they're feeling. Parents often first notice behavioral changes—a child who was eating well suddenly refuses food, or a previously content baby becomes fussy and inconsolable. Understanding these signs helps parents respond appropriately and determine whether home care is sufficient or medical attention is needed.

The way mouth pain presents varies significantly with age. Infants primarily communicate discomfort through crying, changes in feeding behavior, and physical symptoms like drooling. As children develop language skills, they become better able to point to or describe where it hurts. However, even verbal toddlers may struggle to articulate mouth pain specifically, often saying their "face hurts" or simply refusing to eat without explanation.

Drooling is one of the most reliable indicators of mouth pain in young children. While some drooling is normal during teething, a sudden increase in drool production—especially when accompanied by other symptoms—often signals mouth discomfort. The body produces extra saliva in response to oral irritation, and young children haven't yet developed the automatic swallowing reflex that manages this excess.

Common Signs in Infants (0-12 months)

Infants with mouth pain typically demonstrate a cluster of symptoms that, when recognized together, point clearly to oral discomfort. The most obvious sign is a change in feeding behavior. A breastfed baby may latch briefly, then pull away crying. A bottle-fed infant might refuse the nipple entirely or take much smaller amounts than usual. This feeding resistance can be particularly concerning for parents, but understanding that it's a response to pain—not a rejection of food—helps guide appropriate intervention.

Physical examination of the mouth often reveals the source of discomfort. Swollen, red gums in a teething infant are easily visible when you gently lift the lip. White patches might indicate thrush, while small ulcers or blisters point to viral infections. Parents should feel comfortable looking inside their child's mouth regularly, both to monitor for problems and to help children become accustomed to oral examinations.

• Refusing to nurse or take a bottle: Brief latching followed by crying or complete refusal
• Excessive drooling: Significantly more than usual, often soaking through bibs
• Chewing on hands or objects: Seeking counter-pressure for teething discomfort
• Fussiness and irritability: Especially during feeding times or at night
• Low-grade fever: Slight temperature elevation (below 38°C/100.4°F) with teething
• Disrupted sleep: Waking more frequently or having trouble settling

Signs in Toddlers and Older Children

Children aged two and older can often verbalize that something hurts, though they may not always identify the exact location. A toddler might complain that eating hurts, that their teeth hurt, or simply cry while pointing to their face. Parents should take these complaints seriously and conduct a visual examination of the mouth, looking for obvious causes like sores, swelling, or tooth damage.

Behavioral changes remain important indicators even in verbal children. A child who normally loves crunchy foods suddenly wanting only soft items, or one who starts avoiding cold drinks, may be experiencing tooth sensitivity or mouth sores. Changes in speech—particularly reluctance to talk or a different speaking pattern—can indicate pain from tongue or cheek sores.

What Causes Mouth Pain in Children?

The most common causes of mouth pain in children are teething (in infants), mouth sores or ulcers (aphthous ulcers), viral infections like hand-foot-and-mouth disease and herpes, thrush (oral candidiasis), tooth decay (cavities), and dental injuries. Each cause has distinct characteristics and requires different approaches to treatment.

Understanding the underlying cause of your child's mouth pain is essential for providing appropriate care and knowing when professional help is needed. While many causes resolve on their own with supportive care, some require medical or dental intervention. The child's age, accompanying symptoms, and the appearance of any visible mouth changes all provide clues to the likely cause.

Parents often worry that any mouth pain signals a serious problem, but the reality is that most causes of pediatric mouth pain are benign and self-limiting. However, this doesn't diminish the importance of proper assessment and appropriate comfort measures. A child in pain deserves relief, regardless of whether the underlying cause is "serious" in medical terms.

Teething (Tooth Eruption)

Teething is by far the most common cause of mouth pain in infants and young toddlers. The first teeth typically begin emerging around six to eight months of age, though this varies considerably—some babies get teeth as early as three months, while others may not see their first tooth until after their first birthday. All variations within this range are normal and not a cause for concern.

The teething process involves teeth cutting through the gum tissue, which naturally causes inflammation and discomfort. This is why the gums appear red and swollen before a tooth emerges. The pressure of the tooth pushing against the gum tissue creates a sensation that babies instinctively try to relieve by biting and chewing on objects. This is not a behavioral problem—it's a logical response to the physical sensation they're experiencing.

An important clarification: research consistently shows that teething does not cause high fever, diarrhea, or significant illness. While mild temperature elevation (below 38°C/100.4°F) can occur due to inflammation, true fever suggests another cause and should be evaluated. The timing of teething often coincides with when babies lose maternal antibody protection and begin encountering common illnesses, which may explain why these symptoms have been historically attributed to teething.

The complete set of 20 primary (baby) teeth usually emerges by age two to three. The most uncomfortable periods are often when molars erupt, as these larger teeth cause more tissue disruption. Some children seem to barely notice teething, while others experience significant discomfort with each new tooth—this variation is normal and doesn't indicate anything about the child's pain tolerance or future dental health.

Mouth Sores and Ulcers (Aphthous Ulcers)

Aphthous ulcers, commonly called canker sores, are small, painful sores that develop on the soft tissues inside the mouth—the inner cheeks, lips, gums, and tongue. They appear as round or oval lesions with a whitish or grayish center surrounded by a red border. Unlike cold sores, aphthous ulcers occur inside the mouth and are not caused by herpes virus.

The exact cause of aphthous ulcers remains unclear, but several factors appear to trigger them: minor mouth injuries (from biting the cheek or aggressive brushing), acidic or spicy foods, stress, nutritional deficiencies (particularly iron, B12, or folate), and certain underlying conditions. They tend to run in families, suggesting a genetic component to susceptibility.

These sores typically heal on their own within one to two weeks without treatment. The first few days are usually the most painful, with gradual improvement thereafter. While uncomfortable, aphthous ulcers don't indicate serious disease and don't require antibiotic treatment. Recurrent aphthous ulcers—those that appear frequently—may warrant investigation for underlying nutritional deficiencies or other conditions.

Hand, Foot, and Mouth Disease

Hand, foot, and mouth disease (HFMD) is a common viral infection that causes painful mouth sores along with a characteristic rash on the hands and feet. It primarily affects children under ten years of age and is most common in daycare and preschool settings due to the close contact between children. The illness is caused by coxsackievirus, most commonly coxsackievirus A16.

The mouth sores of HFMD typically appear as small blisters that quickly ulcerate, creating painful open sores. They commonly affect the tongue, gums, and inside of the cheeks. These sores can make eating and drinking quite painful, leading to decreased intake and risk of dehydration. The skin rash—small red spots or blisters on the palms, soles, and sometimes buttocks—usually appears around the same time as the mouth sores.

HFMD is highly contagious and spreads through respiratory droplets, fecal contamination, and fluid from the blisters. The incubation period is typically three to six days. Most children recover fully within seven to ten days without specific treatment, though maintaining hydration during the acute phase is essential. There is no vaccine for HFMD, and children can catch it multiple times from different viral strains.

Oral Herpes (Cold Sores)

Herpes simplex virus type 1 (HSV-1) causes oral herpes, which can manifest as cold sores on the lips or as a more extensive infection inside the mouth (herpetic gingivostomatitis). The primary infection—the first time a child encounters the virus—often causes more severe symptoms than subsequent outbreaks. Many children acquire HSV-1 during early childhood through contact with infected family members.

Primary herpetic gingivostomatitis can cause extensive painful sores throughout the mouth, accompanied by fever, swollen gums, and significant discomfort. Children may refuse to eat or drink due to the pain, making dehydration a real concern. The illness typically lasts seven to fourteen days. After recovery, the virus remains dormant in nerve cells and can reactivate later as cold sores, usually triggered by stress, illness, or sun exposure.

Unlike aphthous ulcers, herpes is contagious. During active outbreaks, children should avoid sharing utensils, cups, and towels with others. The virus spreads through direct contact with sores or infected saliva. While herpes cannot be cured, antiviral medications can help if given early in an outbreak, particularly in severe cases or in immunocompromised children.

Thrush (Oral Candidiasis)

Thrush is a fungal infection caused by Candida yeast, which normally lives in the mouth in small amounts. When the balance of microorganisms is disrupted—often by antibiotic use, illness, or in young infants whose immune systems are still developing—Candida can overgrow and cause infection. Thrush is particularly common in babies under six months of age.

The hallmark of thrush is white, cottage cheese-like patches on the tongue, inside of the cheeks, and sometimes the roof of the mouth or gums. Unlike milk residue, these patches cannot be easily wiped away, and attempting to remove them may cause bleeding of the underlying tissue. The mouth tissue underneath may appear red and irritated. Some infants with thrush become fussy during feeding, while others seem unbothered.

Thrush requires treatment with antifungal medication, usually nystatin oral suspension applied directly to the mouth. Treatment typically continues for several days after symptoms resolve to prevent recurrence. Breastfeeding mothers may need simultaneous treatment for nipple thrush to prevent passing the infection back and forth. Good hygiene—sterilizing bottles, pacifiers, and pump parts—helps prevent reinfection.

Tooth Decay (Dental Caries)

Tooth decay can cause significant mouth pain, particularly when cavities become deep enough to reach the nerve (pulp) of the tooth. Early cavities may cause no symptoms at all, but as decay progresses, children typically develop sensitivity to sweet, cold, or hot foods and drinks. Advanced decay can cause constant, severe pain and may lead to dental abscesses—serious infections that require urgent treatment.

Primary (baby) teeth are susceptible to decay and need the same preventive care as permanent teeth. The concept that baby teeth "don't matter because they'll fall out anyway" is a dangerous misconception. Untreated decay in baby teeth can cause pain, infection, difficulty eating, and damage to the developing permanent teeth beneath them. Early childhood caries (formerly called "baby bottle tooth decay") is entirely preventable with proper oral hygiene and feeding practices.

Risk factors for early childhood tooth decay include prolonged bottle feeding (especially at night), frequent consumption of sugary drinks or foods, inadequate tooth brushing, and lack of fluoride exposure. Children who fall asleep with bottles containing anything other than water are at particularly high risk, as the sugary liquid pools around the teeth throughout the night.

When Should You Seek Medical Care for Mouth Pain?

Seek medical care if your child has high fever (over 38.5°C/101°F), difficulty swallowing or breathing, facial swelling, visible tooth damage, mouth sores lasting more than two weeks, or signs of dehydration (no wet diapers for 8+ hours, no tears when crying). Call emergency services immediately for any breathing difficulty or severe facial/throat swelling.

Most cases of mouth pain in children resolve on their own with supportive care at home. However, certain symptoms indicate the need for professional evaluation. Knowing these warning signs helps parents make appropriate decisions about when to seek care, avoiding both unnecessary emergency visits and dangerous delays in treatment.

The most concerning symptoms relate to airway compromise. Swelling in the mouth or throat can potentially obstruct breathing, which is a medical emergency. Any difficulty breathing, drooling with inability to swallow, or severe swelling of the face, lips, or throat requires immediate emergency care. These symptoms are rare but serious enough to warrant urgent attention.

Dehydration is the most common complication of mouth pain in children, occurring when pain prevents adequate fluid intake. Young children, especially infants, can become dehydrated relatively quickly. Signs of dehydration include decreased urine output (fewer wet diapers), dry mouth and lips, no tears when crying, sunken eyes, and lethargy. Mild dehydration can often be managed at home with careful attention to fluid intake, but moderate to severe dehydration requires medical intervention.

Seek immediate emergency care if your child has:

• Difficulty breathing: Labored breathing, wheezing, or stridor (high-pitched breathing sound)
• Unable to swallow: Drooling excessively because they cannot swallow saliva
• Severe throat or facial swelling: Visible swelling that's rapidly worsening
• Signs of severe dehydration: Unresponsive, very weak, or no urine for 12+ hours

Contact a healthcare provider or dentist if:

• Fever above 38.5°C (101°F): Especially if persistent or accompanied by other symptoms
• Difficulty drinking: Not taking enough fluids to stay hydrated
• Mouth sores lasting more than 2 weeks: May indicate underlying condition
• Visible tooth damage: Broken, loose, or knocked-out tooth from injury
• Facial swelling: Particularly if warm to touch or associated with tooth
• White patches in mouth: Possible thrush requiring treatment
• Child under 6 months: Any mouth symptoms warrant professional evaluation

How Can You Help Your Child at Home?

To relieve mouth pain at home: offer cold drinks, ice pops, or soft foods like yogurt; provide a chilled (not frozen) teething ring for teething pain; give age-appropriate pain medication (acetaminophen from 3 months, ibuprofen from 6 months); and ensure adequate hydration. Getting fluids is more important than solid food when a child has mouth pain.

Home management of mouth pain focuses on two primary goals: providing comfort and maintaining adequate hydration. Pain relief allows children to eat and drink more comfortably, which in turn prevents the most common complication of mouth pain—dehydration. Simple interventions are often highly effective, and most children with mouth pain can be successfully managed at home.

Temperature plays an important role in pain management. Cold foods and drinks provide natural pain relief by numbing the affected tissues. This is why cold teething rings work well for teething babies and why ice pops can be so soothing for children with mouth sores. The cold also reduces inflammation, providing dual benefit. However, some children may prefer room-temperature foods, particularly if they have tooth sensitivity to cold.

The texture of foods matters when a child has mouth pain. Soft, smooth foods are generally better tolerated than rough, crunchy, or acidic items. Mashed potatoes, yogurt, smoothies, and soft pasta are often accepted when other foods are refused. Avoid citrus fruits, tomatoes, and spicy foods, which can irritate mouth sores. If your child will only take liquids, that's acceptable short-term—hydration is the priority.

Teething Relief Strategies

Teething rings remain one of the most effective tools for teething discomfort. The pressure from chewing on a firm object provides counter-stimulation that reduces the sensation of pain from the erupting tooth. Solid teething rings (not liquid-filled, which can break and leak) can be chilled in the refrigerator for added soothing effect. Never freeze teething rings, as extreme cold can damage delicate gum tissue.

A clean, cold washcloth offers a simple alternative to commercial teething rings. Wet a clean washcloth, wring out excess water, and chill it in the refrigerator. The texture provides something to chew on, and the cold offers numbing relief. Some parents twist the cloth to create different textures for the baby to explore. Wash used cloths daily to prevent bacterial growth.

Gentle gum massage can provide relief for some babies. Using a clean finger, gently rub the swollen gum area where the tooth is erupting. The pressure can help ease discomfort, and some babies find this very soothing. This technique also helps babies become comfortable with having their mouth touched, which supports future oral hygiene practices.

Managing Mouth Sores

For children with mouth sores from viral infections or aphthous ulcers, pain relief and hydration are the main treatment goals. Cold foods and drinks help numb the pain—ice pops, chilled fruit purees, and cold milk are often well-accepted. Avoid acidic foods (citrus, tomatoes, vinegar-based dressings) and salty or spicy foods, which can intensify pain from open sores.

Maintaining oral hygiene remains important even when the mouth is sore. Use a soft-bristled toothbrush and be gentle around affected areas. If brushing is too painful, have your child swish with plain water after eating to remove food debris. Once the acute phase passes, return to normal brushing routines.

Over-the-Counter Pain Medications

When non-medication approaches aren't providing adequate relief, age-appropriate pain medication can help. Acetaminophen (paracetamol) is safe for children from three months of age and provides effective pain relief. Ibuprofen is safe from six months of age and offers both pain relief and anti-inflammatory effects. Always follow dosing instructions based on your child's weight, not just age.

Both medications are available in liquid formulations designed for children. Many pharmacies can provide dosing syringes or cups to ensure accurate measurement. Never exceed the recommended dose, and be aware of the dosing interval—acetaminophen every 4-6 hours, ibuprofen every 6-8 hours. If you're unsure about dosing, contact your pharmacist or healthcare provider.

How Can You Prevent Mouth Pain in Children?

Prevent mouth pain by maintaining good oral hygiene (brushing twice daily from first tooth), avoiding prolonged bottle feeding, limiting sugary foods and drinks, ensuring adequate nutrition, and practicing good hand hygiene to prevent viral infections. Regular dental visits starting by age one help identify and address problems early.

While some causes of mouth pain like teething are unavoidable parts of normal development, many others are preventable through consistent oral hygiene practices and healthy lifestyle habits. Establishing good oral care routines early in life sets children up for better dental health throughout their lives and can prevent significant pain and dental problems.

Oral hygiene should begin before the first tooth even appears. Gently wiping an infant's gums with a clean, damp cloth after feedings helps establish the habit of oral care and removes milk residue. Once the first tooth erupts, begin brushing twice daily with a soft-bristled brush and a rice-grain-sized smear of fluoride toothpaste. Increase to a pea-sized amount around age three.

Diet plays a crucial role in oral health. Frequent exposure to sugar—whether from candy, juice, milk, or formula left in the mouth overnight—feeds the bacteria that cause tooth decay. Limit juice to mealtimes, avoid putting children to bed with bottles containing anything other than water, and offer water as the primary beverage between meals. These simple habits significantly reduce cavity risk.

Key Prevention Strategies

• Start brushing early: Begin at first tooth with fluoride toothpaste
• Establish dental home: First dental visit by age one or within six months of first tooth
• Limit sugar exposure: Avoid frequent snacking on sugary foods and drinks
• No bottles in bed: Only water in bottles at sleep time to prevent decay
• Practice hand hygiene: Regular handwashing prevents viral infections
• Ensure balanced nutrition: Adequate vitamins and minerals support oral health