Skip to Content

What does baby yeast infection look like?

A yeast infection, also known as thrush, is a common infection caused by an overgrowth of yeast in or on a baby’s body. The most common locations for yeast infections in babies are the mouth (oral thrush) and diaper area (diaper rash). Yeast infections can be uncomfortable for babies and concerning for parents, but they are generally not serious and can be easily treated. Recognizing the signs and symptoms of a yeast infection is key to getting your baby the right treatment.

What Causes Yeast Infections in Babies?

Yeast, specifically Candida yeast, are fungi that normally live on human skin and mucous membranes without causing issues. However, when conditions allow them to overgrow, they can cause infection. Some common causes and contributing factors to yeast overgrowth in babies include:

  • Weakened immune system – Babies under 6 months old have immature immune systems that are still developing the ability to keep yeast growth in check.
  • Use of antibiotics – Antibiotics kill off good bacteria that help limit yeast overgrowth, allowing yeast to thrive.
  • Warm, moist environments – Yeast grows best in warm, moist areas like the mouth, diaper area, and skin folds.
  • Compromised skin integrity – Yeast can more easily enter the body through damaged skin.
  • Exposure during birth – Babies can be exposed to yeast during vaginal delivery.

While yeast infections themselves are not contagious, babies can pass thrush back and forth through breastfeeding. Some babies are also more prone to yeast infections due to risk factors like prematurity, illness, or compromised immunity. However, in most cases, there is no specific cause of a baby’s yeast infection.

Oral Thrush Symptoms

Oral thrush causes creamy white lesions to develop in a baby’s mouth. Some other symptoms of oral thrush include:

  • White patches on the inner cheeks, tongue, gums, lips, or palate
  • Loss of taste
  • Redness or soreness in or around the mouth
  • Difficulty feeding or refusing to eat
  • Fussiness during feeding
  • Excessive salivation or drooling

In mild cases, oral thrush may not cause any noticeable symptoms. Yeast can spread to the throat in more severe infections, causing pain or difficulty swallowing. Babies with oral thrush may also develop a diaper rash at the same time.

What does oral thrush look like?

Oral thrush causes distinct white lesions that coat the inside of the mouth and tongue. These creamy or yellowish white patches may look like spilled milk or cottage cheese. While they can be wiped away, the lesions often quickly return. They are usually not painful and may only be noticed during examination of the baby’s mouth.

Diaper Rash Symptoms

Yeast is a common cause of diaper rash, resulting in a distinctive bright red rash in the diaper area. Other symptoms of a yeast diaper rash include:

  • Rash confined to the skin within the diaper area, including genitals, buttocks, and upper thighs
  • Sharply defined rash borders and satellite lesions
  • Beefy red rash with tiny red pimples or pustules on the surface
  • Extreme rash redness, often described as “tomato red”
  • Minimal fluid or oozing from rash
  • Mild skin irritation, burning, or pain

What does a yeast diaper rash look like?

A yeast diaper rash has a very distinctive bright red, beefy red, or red-orange appearance. It will be sharply bordered in the diaper area creases. Tiny pimples or pustules may dot the surface of the rash. The skin may appear shiny. As the rash heals, it often peels or flakes.

Other Locations of Yeast Infections

While oral thrush and diaper rash are most common, yeast can overgrow and cause infection in other moist areas of a baby’s body, leading to additional symptoms:

Yeast infection under breast

  • Occurs under breast folds in breastfed babies
  • Bright red rash with satellite lesions
  • May be swollen, painful, or ooze fluid

Yeast infection in skin folds

  • Affects deep skin folds like the neck, armpits, and groin
  • Red rash with defined borders
  • May see pustules or small blisters
  • Area feels raw or sore

Yeast infection on the scalp (cradle cap)

  • Greasy, yellow, scaly patches on the scalp
  • May have redness and crusting if more severe
  • Hair loss in patches may occur

Yeast infection in the diaper area

  • Involvement of the genitals and buttocks
  • Beefy red rash with satellite lesions
  • Pimples or pustules scattered on the rash
  • Shiny appearance with defined borders

When to See a Doctor

In most cases, mild yeast infections can be safely treated at home using over-the-counter antifungal creams and ointments. However, you should contact your pediatrician if:

  • The rash or lesions do not improve within 1 week of using over-the-counter treatment
  • The infection worsens or spreads
  • Your baby has signs of systemic infection like fever, sluggishness, or poor feeding
  • The yeast infection recurs frequently
  • Your baby is under 4 weeks old

Your doctor can prescribe oral antifungal medication or provide guidance on managing stubborn yeast infections. Prompt medical attention is important for rashes affecting a young infant or rashes that do not respond to initial treatment.

Diagnosing a Yeast Infection

Doctors can often make a diagnosis of oral thrush or yeast diaper rash based on the appearance and location of the rash. However, they may use the following tests to confirm a yeast infection or rule out other causes:

  • Microscopic examination – Scraping a small sample of the lesions to look for yeast under a microscope
  • Fungal culture – Growing the yeast organisms from a swab sample to identify the specific type
  • Skin biopsy – Rarely needed, but examines a small sample of rash tissue for yeast

If other bacterial or viral infections are suspected, your doctor may order a viral culture or bacterial culture. Blood tests are not typically needed unless the baby has a fever or other concerning symptoms.

Treating Yeast Infections in Babies

Most simple yeast infections can be treated at home using antifungal ointments, creams, or powders that are readily available over-the-counter. Common antifungal ingredients include nystatin, miconazole, clotrimazole, and terbinafine. Treatment guidelines include:

  • Oral thrush – Antifungal oral suspension or gel painted on white lesions after feedings and before bedtime. May also treat mother’s breasts/nipples if breastfeeding.
  • Diaper rash – Antifungal cream or ointment applied thickly at each diaper change. Use barrier creams/pastes to prevent further irritation.
  • Other skin infections – Antifungal cream applied to affected area twice daily for 1-2 weeks.

In addition to topical antifungal treatment, there are several natural and home remedies that may help clear up a yeast infection. These include:

  • Probiotics to restore good gut and skin bacteria
  • Coconut oil has antifungal properties
  • Tea tree oil may reduce yeast overgrowth
  • Vinegar rinses can kill yeast in the mouth
  • Yogurt contains probiotics to fight yeast
  • Garlic has antifungal abilities

For severe, chronic, or recurrent yeast infections, prescription oral antifungal medication may be needed. Fluconazole, itraconazole, or ketoconazole are sometimes used for difficult diaper rashes or oral thrush. The medication must be prescribed by a doctor.

In addition to medication, careful hygiene and prevention methods may be needed to stop recurrences. This includes frequent diaper changes, barrier creams, breast care for nursing mothers, and sterilization of any shared feeding items. Proper identification and prompt treatment of yeast infections in babies provides symptom relief and prevents complications.

Complications of Yeast Infections

Yeast infections in babies are typically benign and resolve with simple treatment. However, complications can sometimes occur, especially if treatment is delayed or infections are widespread, severe, or recurrent. Potential complications include:

  • Oral thrush can spread down the throat causing painful swallowing or throat spasms.
  • Widespread diaper rash with yeast can lead to a secondary bacterial infection.
  • In breastfeeding mothers, yeast can cause symptoms like nipple/breast pain, cracked nipples, and blocked ducts.
  • Chronic yeast infections may be a sign of an undiagnosed immune deficiency.
  • Babies can develop nutritional deficiencies if oral thrush limits their ability to feed.
  • Candida yeast can enter the bloodstream and spread to organs in rare, severe cases.

Parents should monitor for any worsening of a yeast infection and contact the pediatrician promptly if the baby develops a fever, has difficulty feeding, or does not improve with initial treatment. Proper diagnosis and management of yeast infections reduces the risk of complications.

Preventing Yeast Infections in Babies

While yeast infections may sometimes be inevitable, there are several strategies parents can use to help prevent them:

  • Change wet, soiled diapers frequently to avoid skin irritation.
  • Allow diaper area to air dry after changes to reduce moisture.
  • Use barrier cream at diaper changes but avoid excessive use.
  • Wash and sterilize any toys or pacifiers regularly.
  • Avoid shared feeding utensils and wash all items that touch baby’s mouth.
  • If breastfeeding, treat any nipple/breast thrush in mother.
  • Discuss optimal dosing of antibiotics with your pediatrician.
  • Watch for early signs of yeast overgrowth and treat promptly.

Avoiding excessive moisture, meticulous hygiene, and maintaining skin integrity can help reduce the risk of yeast overgrowth. However, yeast infections may still occur even with excellent preventive care. Contact your pediatrician if your baby develops any signs of an oral thrush or diaper rash.

When to Expect Improvement

You can expect to see improvement in your baby’s yeast infection within a few days of starting antifungal treatment. However, rashes and lesions may take 1-2 weeks to fully clear.

Oral thrush improvement timeline:

  • Pain relief: Within 24-48 hours
  • Decreased lesion/rash: 3-5 days
  • Complete resolution: 7-14 days

You should see reduced redness, less plaque, and minimal white patches within several days of oral thrush treatment. Feeding may become easier for your baby as the lesions heal.

Diaper rash improvement timeline:

  • Less irritation/pain: 1-3 days
  • Fading of rash: 3-5 days
  • Complete clearance: 7-14 days

The bright red hue should fade over several days. Pimples and satellite lesions will gradually clear. However, it may take up to 2 weeks for all scaling and skin peeling to resolve after a yeast diaper rash.

Monitor progress closely and contact your pediatrician if your baby’s symptoms do not improve within 1 week of treatment. Recurrence is common within the first 1-2 months if hygiene and preventive steps are not taken. Discuss any concerns with your baby’s doctor.


Yeast infections like oral thrush and diaper rash are a common affliction in babies under one year of age. The trademark white mouth lesions and bright red diaper rash are the classic signs of yeast overgrowth. While uncomfortable, yeast infections are typically not serious. With antifungal treatment and proper hygiene, symptoms generally resolve within 1-2 weeks without complications. Paying attention to preventive care and recognizing the early signs can help limit yeast infections in babies. Speak to your pediatrician if you have any concerns about your baby’s symptoms or they do not respond promptly to topical antifungal treatment. With some care and observation, yeast can be managed to provide your baby comfort and relief.