Thumb sucking is a common habit of young children because it provides comfort and safety. Many children start sucking their thumbs in the womb and continue this habit during the baby and toddler. If your baby often sucks on the thumb, you may notice that his skin is dry, red, cracked, or has a rash. Most likely, it's just a side effect of sucking the thumb, but once you have all the facts in hand, you can discuss the appropriate treatment plan with his pediatrician.

Thumb sucking
According to the New York University Children's Research Center, three-quarters of babies suck their thumbs or The first time I saw the finger of life. Thumb sucking is an activity that helps soothe and entertain your child. Unless your child still sucks his thumb after his fifth birthday, don't worry. Sucking your thumb for a long time can cause dental problems and may make it easier for your child to tease at school. Dry, chapped and red skin is another complaint because your child's skin is often in contact with his saliva.
Skin Problems
Frequent sucking of your thumb can cause your baby's skin to become very dry, which can lead to a flaky and red appearance. According to Jennifer Trachtenberg, author of Goodbaby, Bad Habits: The RealAge Guide to Raising Healthy Children, it can cause a rash when the baby's skin is often in contact with his saliva. If he drools while sucking his thumb, his baby may also have a rash around his mouth. This type of rash develops due to frequent changes between the wet and dry environment experienced by the baby's skin.
Prevention and Treatment
Keeping your child's thumb and skin around his mouth dry is as possible. Wipe off any drooling on your face as soon as possible and keep your thumb dry when he is not sucking. The rash can be prevented by reducing the time it takes for the skin to contact the baby's saliva. If your baby has a rash, keep the area clean. Apply a mild lotion or cream to the rash to keep it moist and promote healing. If you keep your baby's face moisturized, it can helpHelp reduce his chances of getting a rash.
Notes
If your baby's rash does not improve or worsen within two or three days, talk to his pediatrician. Infants may develop a rash for a variety of reasons, and only your doctor can determine the cause. If your baby often has no rash, consider what he eats or drinks before sucking his thumb. Certain foods and beverages may irritate the skin and cause a rash.