Yes, you can use witch hazel on a baby. Witch hazel is known for its anti-inflammatory and astringent properties, which make it useful in treating skin irritations like diaper rash or eczema. However, it's important to dilute the witch hazel with water before applying it to your baby’s skin as undiluted witch hazel may be too strong for their delicate skin. Additionally, always consult your pediatrician prior to using any products on your child’s skin. When used properly and safely, witch hazel can provide relief from itching and irritation associated with common infant ailments such as diaper rash or eczema.