Causes of a blocked tear duct

Tears flow from the eye to the nose through a narrow tube called the tear duct. This tube can get blocked.

We’re not sure what causes a blocked tear duct, but it’s probably a plug of mucus or cells that has been left behind during the baby’s development in the uterus. The block is usually present at birth, but it might not be obvious until your baby is around one month old.

Blocked tear ducts are quite common. About 1 in 20 babies are born with a block in one or both of their tear ducts.

Symptoms of a blocked tear duct

If your baby has a blocked tear duct, his eye will be watering constantly. When he wakes up, he might have an even worse discharge from his eye. You might hear these symptoms called ‘watering eyes’ and ‘sticky eyes’.

Other than the watering and discharge, your baby’s eye is perfectly normal.

When to see your doctor about blocked tear duct symptoms

You should take your child to the GP if:

  • your baby’s eye or eyes look red
  • you notice other symptoms like sensitivity to light or your baby constantly squeezing her eyes shut
  • there’s a greenish discharge from your baby’s eye – this might mean it’s infected
  • the tear duct is still blocked after your child has turned one year old.

Treatment for a blocked tear duct

A blocked tear duct usually gets better by itself, when the lower end of the tear duct opens up. This usually happens by the time your baby turns one year old.

If the tear duct is still blocked after your child reaches six months of age, your GP might refer you to a specialist. The specialist might use a fine probe under general anaesthetic to open up the duct.