How to get my child to stop sucking their thumb

By Chelsey Koga, a contributing writer for Sharp Health News and a senior digital producer for Sharp HealthCare.

During a prenatal ultrasound for my youngest daughter, I remember images of her with a hand near her face. Soon after she was born, her left thumb went into her mouth and rarely comes out. Now she’s 2, and I’m worried it will be harder to wean her from her thumb than it was to get my oldest daughter to give up her pacifier at 3.

Dr. Ricardo Indacochea, a pediatrician with Sharp Rees-Stealy Medical Group, explains why children suck their thumbs and shares tips on how to address the habit.

Why does my child suck their thumb?
Thumb sucking is very common and a normal part of development. “If it persists past the nursing and bottle-feeding stage, it can become a learned behavior,” says Dr. Indacochea. “Kids suck their thumb to self-soothe, much like they use a pacifier, or hold a blanket or stuffed animal.”

When should children stop sucking their thumb?
“Ideally, the issue should be addressed before the age of 3 because breaking the habit becomes more of a challenge after that,” says Dr. Indacochea.

However, before trying to break the habit, consider the following questions:

• How often does my child suck their thumb? Is it mostly at home, before a meal or bedtime, or while sitting on the couch quietly? If so, then it is probably not worth the effort to curb the behavior. You can let your child stop when they’re ready.

• How big of a priority is it? Because thumb sucking usually goes away on its own, you might want to focus your energy instead on activities that foster healthy development, such as reading books or increasing physical activity.

How do I get my child to break the habit?
If you decide that you would like to try to stop your child’s thumb sucking, Dr. Indacochea recommends the following tips:

• Set up a positive reward system, much like parents do for toilet training. Except the reward would be earned when your child does not suck their thumb.

• Use words of encouragement to help a child who’s a little older (4 to 5 years old) break the habit. Tell them that you are not worried about their thumb sucking because you know that one day they will be a big kid and will not want to do it anymore.

• Determine if there are sources of stress or anxiety in your child’s life and address them. Thumb sucking could be your child’s form of managing stress.

• As a last resort, apply a bad tasting substance to the thumb. This tends to work better in older children who are motivated to stop on their own.

Are there health risks with thumb sucking?
If your child continues sucking their thumb into elementary school, they could face dental issues as their permanent teeth come in. These include a gap between the top and bottom teeth, a crossbite or an overbite. Medical risks are rare, but thumb sucking might cause finger infections or deformities.

If you have concerns about your child’s thumb sucking, talk with their pediatrician.

“As a parent, I understand the frustration that comes with certain learned childhood behaviors. They can be stressful in the moment,” says Dr. Indacochea. “As a pediatrician, I understand the long-term implications of these behaviors. When it comes to thumb sucking, I reassure parents that this will get better on its own. It’s exceedingly rare that any of my 5- or 6-year-old patients are still sucking their thumbs.”