Meta Description: Baby has a runny nose and is fussy—is it a cold or teething? Learn the key differences in symptoms, how to provide the right relief, and when to call the doctor.
That familiar fussiness sets in. Your baby is drooling more than usual, has a runny nose, and is pulling at their ear. You reach for the mental checklist: Could it be a tooth? Or are we coming down with yet another daycare bug? In the fog of new-parent exhaustion, distinguishing between common teething discomfort and the onset of a genuine illness can feel impossible. You don’t want to overlook a cold that needs care, but you also don’t want to stress over every symptom if it’s just a new tooth on the way.
This confusion is universal. Teething and colds share a surprising overlap of symptoms, and because babies teeth constantly during their first two years, it’s easy to blame every off day on a new tooth. However, mistaking an illness for “just teething” can delay needed comfort or medical attention.
Take a deep breath. You are about to become a skilled detective in your baby’s health. This guide will provide you with a clear, symptom-by-symptom comparison, a simple framework for deciding what you’re likely dealing with, and tailored advice for providing the right kind of relief. Let’s cut through the confusion and help you respond with confidence.
The Overlap Problem: Why It’s So Hard to Tell
Teething and upper respiratory infections (colds) are both extremely common in infancy. Their symptoms can mirror each other because:
- Shared Pathways: Discomfort in the gums can radiate through the same nerve pathways as ear pain, leading to ear pulling in both scenarios.
- Immune System Timing: The period of intense teething (6-24 months) coincides with the time a baby’s maternal antibodies are waning and they’re building their own immune system, making them more susceptible to frequent colds.
- Non-Specific Signs: Fussiness, sleep disruption, and changes in appetite are hallmarks of any discomfort in a baby.
The key is to look for clusters of symptoms and understand which symptoms are strongly tied to one cause and not the other.
The Symptom Detective: A Side-by-Side Comparison
Use this chart as your primary reference. It breaks down each symptom and its likely origin.
| Symptom | More Likely TEETHING | More Likely a COLD or ILLNESS | Key Differentiators |
|---|---|---|---|
| Fever | Low-grade only. A slight elevation, never above 100.4°F (38°C). | Can be present and higher. Often 100.4°F (38°C) or above. | A true fever (≥100.4°F) is NOT caused by teething. This is the most critical distinction. |
| Runny Nose | Clear, watery mucus. Caused by increased saliva/drool draining into the nasopharynx. | Can start clear but often becomes thick, yellow, or green mucus as the cold progresses. | Color & consistency. Teething snot is like water. Cold snot is like glue. |
| Cough | A mild, occasional cough from excess drool trickling down the throat (“post-nasal drip” from saliva). | A more persistent, frequent cough. Can be dry or wet/chesty. May worsen at night. | Frequency and type. A constant or deep cough signals illness. |
| Fussiness & Crying | Intermittent. Often worse in the evening. Can be soothed by chewing/pressure on gums. | More constant, pervasive. May be accompanied by a “sick” cry (whiny, weak) and is harder to soothe. | Soothe-ability. If gum pressure provides clear relief, it points to teething. |
| Drooling | Profuse and constant. Soaking through shirts and causing facial rash. | Can be present but is usually not the dominant, standout symptom. | The “Waterfall” Test. If it’s a faucet, think teeth. |
| Gum Symptoms | Red, swollen, bulging gums. Visible tooth bud. Baby urgently gnaws on everything. | Gums look normal. No increased desire to chomp. | The presence of gum inflammation is a teething giveaway. |
| Appetite | May refuse solids or bottles due to gum pain, but usually still interested in breastfeeding (sucking is comforting). | May refuse all feeds (breast, bottle, solids) due to general malaise and/or nasal congestion. | Breastfeeding as a clue. A teething baby often nurses for comfort; a sick baby may not. |
| Sleep | Disrupted due to pain, but baby can often be resettled with comfort. | Severely disrupted due to congestion, coughing, or general discomfort. Harder to resettle. | |
| Diarrhea | Loosely associated, not proven. Excess swallowed saliva might loosen stools slightly. | Can occur, especially with certain viruses. May be more pronounced. | The AAP states there’s no proven causal link between teething and diarrhea. |
| Ear Pulling | Common, due to referred gum pain. | Common, due to fluid/pressure from a true ear infection. | Context is key. With fever and extreme fussiness, suspect ear infection. With drooling and gnawing, suspect teeth. |
| Rash | Drool rash on chin, cheeks, and neck from constant moisture. | Not typical unless from a specific virus (like a body rash with roseola). | Location. Facial = likely teething. Body = likely viral. |
The Decision Tree: Putting the Clues Together
When you’re in the moment, ask yourself these questions in order:
- Is there a FEVER of 100.4°F (38°C) or higher?
- YES = Likely ILLNESS. Stop here. Manage the fever and monitor for other cold symptoms. A high fever is not from teething.
- NO or LOW-GRADE = Proceed to Q2.
- Are the gums RED, SWOLLEN, and is baby GNAWING violently on everything?
- YES = Strong indicator of TEETHING. Check for profuse drooling.
- NO = Proceed to Q3.
- What is the nature of the RUNNY NOSE and COUGH?
- Clear, watery nose + occasional cough = leans TEETHING.
- Thick, colored mucus + persistent cough = leans COLD.
- Can you SOOTHE the baby by letting them chew on a cold teether or massaging their gums?
- YES, and they calm noticeably = points to TEETHING.
- NO, they remain inconsolable = points to ILLNESS.
The Most Common Scenario: It’s possible for a baby to be teething and catch a cold simultaneously. Their immune system can be slightly taxed by teething, and they put everything in their mouth, exposing them to germs. If symptoms are mixed, always treat the more serious one (the cold/illness) as the priority.
Age-Specific Considerations: What to Expect and When
- 3-6 Months: This is when teething often begins. Colds are also common. Be extra vigilant about fever in this age group, as any fever in a baby under 3 months is an automatic doctor’s visit.
- 6-12 Months: Peak teething time for front teeth and first molars. Also a prime time for first major colds and viruses like RSV. Symptom comparison is most challenging here.
- 12-24 Months: Molars and canines erupt, which can be particularly painful. Toddlers are also more mobile, touching everything and spreading germs. They may be able to point to their mouth or say “hurt,” giving you a clearer clue.
Your Action Plan: Soothing Strategies for Each Cause
If It’s Teething:
- Counter-Pressure: Offer a firm, chilled (not frozen) teething toy, a silicone feeder with frozen fruit, or a clean, cold washcloth to gnaw on.
- Gum Massage: Wash your hands and use a clean finger to gently rub the sore gums.
- Pain Relief: For significant discomfort, use the appropriate dose of acetaminophen (Tylenol) or, for babies over 6 months, ibuprofen (Motrin/Advil). This is especially helpful before bedtime.
- Dry the Drool: Gently pat the chin and cheeks dry throughout the day and use a barrier cream (like petroleum jelly) to protect from drool rash.
If It’s a Cold:
- Humidity: Run a cool-mist humidifier in the baby’s room to ease congestion.
- Saline & Suction: Use saline drops and a nasal aspirator (like the NoseFrida) to clear mucus before feeds and sleep. For a detailed guide, see our post on how to use a NoseFrida correctly.
- Hydration: Offer frequent, small amounts of breast milk, formula, or water (if over 6 months).
- Elevate: Place a towel under the head of the crib mattress to help with post-nasal drip at night.
- Pain/Fever Relief: Use acetaminophen or ibuprofen as needed for fever or general aches. Never give cough/cold medicine to infants.
When to Call the Pediatrician: Red Flags
Regardless of what you think the cause is, contact your doctor if your baby has:
- Fever over 100.4°F (38°C) if under 3 months; over 102°F (38.9°C) if older.
- Fever lasting more than 3 days.
- Symptoms lasting more than 7-10 days without improvement.
- Difficulty breathing, rapid breathing, or wheezing.
- Signs of dehydration (fewer than 4 wet diapers in 24 hours, no tears, dry mouth).
- Extreme lethargy or inability to be awakened easily.
- Not drinking fluids.
- Pulling at ears accompanied by high fever or extreme fussiness (sign of ear infection).
- A rash that spreads or doesn’t blanch when pressed.
A Final Word of Reassurance
The very fact you’re scrutinizing these symptoms shows your incredible care and attentiveness. It’s okay not to have an instant answer every time. Often, a bit of watchful waiting—paired with gentle comfort measures—will reveal the true culprit within 24 hours.
Trust your instincts. You know your baby’s baseline better than anyone. If something feels “off” in a way that doesn’t fit a typical teething or cold pattern, never hesitate to call your pediatrician. That’s what they’re there for. Whether it’s a new tooth or a passing virus, your calm presence and loving comfort are the most powerful medicine your baby can receive.
For a deeper dive on what to expect during the teething journey, see our complete guide on teething symptoms timeline and order.
Your Top 5 “Cold or Teething?” Questions, Answered!
1. Can teething really cause a high fever?
No. This is a crucial myth to bust. The American Academy of Pediatrics (AAP) is clear: teething might cause a very slight increase in body temperature, but it does not cause a true fever (100.4°F or 38°C and above). If your baby has a high fever, it is due to an infection or illness and should be evaluated by a doctor. Blaming a fever on teething can delay treatment for something more serious.
2. My baby has green snot. Does that mean it’s definitely a cold and not teething?
Almost certainly, yes. While teething can produce clear, watery drool and nasal drainage, the moment mucus becomes thickened, yellow, or green, it indicates an immune system response to an infection (viral or bacterial). Green snot is a strong sign of a cold or sinus congestion, not teething.
3. How long do teething symptoms last per tooth?
Active, noticeable symptoms typically occur in the 3-5 days leading up to the tooth breaking through the gum (eruption) and usually subside within a couple of days after the tooth appears. The entire process from first movement under the gum to full emergence can be longer, but the acute fussiness is relatively short-lived per tooth.
4. Is diarrhea a sign of teething or a cold?
It is more reliably a sign of a cold or virus. The AAP states there is no proven causal link between teething and diarrhea. The old theory was that excess saliva upset the stomach, but there’s no evidence. Diarrhea is a common symptom of many childhood viruses. If your baby has significant diarrhea, focus on hydration and consider it an illness, not a teething side effect.
5. Could it be an ear infection instead?
Absolutely, and this is why careful observation is key. Ear pulling, fussiness, and fever are common to both teething and ear infections. Clues that point to an ear infection include: a high fever, symptoms that worsen when lying down, cold symptoms that seem to “improve” but the fussiness remains or gets worse, and severe, inconsolable crying. If you suspect an ear infection, a doctor’s visit is necessary for diagnosis and possible treatment. Understanding all aspects of your baby’s health is interconnected. For instance, managing discomfort, whether from teething or illness, often starts with monitoring their well-being. Our post on how to take a baby’s temperature underarm can ensure you’re tracking symptoms accurately.
