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Clinical clangers: ‘My baby has conjunctivitis again, could you prescribe some eye drops?’

Continuing our series on clinical scenarios that may be mishandled in primary care, Dr Toni Hazell advises how to avoid potential overtreatment in babies with nasolacrimal duct obstruction

You are the duty GP and have been asked by a pharmacy to see an eight-month-old baby, as the parents are repeatedly asking for antibiotic eye drops to treat her conjunctivitis – these drops can’t be issued over the counter for that age. The pharmacist asks if you think this is conjunctivitis or something else – should the child see an ophthalmologist? 

The reality
Obstruction of the nasolacrimal duct, which drains tears from the inner corner of each eye to the inside of the nose, is present in up to one-fifth of all babies.1,2 This can lead to eyes being watery, sticky and appearing irritated, leading parents to suspect conjunctivitis. A key differentiating feature is the lack of redness in the eye.

The issue
If healthcare professionals fail to recognise nasolacrimal duct obstruction we risk overtreating these children with antibiotic eye drops, contributing to antibiotic resistance and unnecessarily distressing the baby and their parents who have to get eye drops into an unwilling infant. When the ‘conjunctivitis’ inevitably recurs, parents will present for more treatment and the cycle is perpetuated. 

The evidence
Guidance from the College of Optometrists states that 5-20% of babies have a persistent membranous obstruction at the opening of the nasolacrimal duct into the nose; this may be unilateral or bilateral.1 Other sources also give figures of between 5% and 30%.3-5 It is difficult to find corresponding figures on rates of acute bacterial conjunctivitis in infants as it is mainly coded and swabbed when it occurs in the neonatal period, because of the risk of more serious infection at that point. But figures we do have include an estimated annual incidence of 1.35% in the US and 1.3% in the UK among people of all ages.6,7 

Avoiding a clanger
Taking a thorough history, listening to the parent, examining and formulating a sensible differential diagnosis will help you avoid overtreatment, as well as not missing a serious cause.

In an otherwise healthy infant aged under one, who has a sticky or watery eye that is not red and who is systemically well, there is no need to rush to label this as bacterial conjunctivitis and treat with antibiotic drops. The incidence figures should make us confident that nasolacrimal duct obstruction is more likely. Explaining this to the parent, perhaps with an information leaflet, can empower them to manage the child at home. Parents can also be reassured that most children grow out of this (70-90% at one year)1,3 and that home management is as simple as keeping the skin clean with cotton wool and water, or using Vaseline to protect sore skin. Massaging the tear duct can help; there are online resources to show them how to do this.2,8

Red flags in a child with ‘conjunctivitis’ include severe pain in the eye (for those old enough to express it), the child being systemically unwell, being immunocompromised and at higher risk of a bacterial infection, or having a serious eye condition. 

For babies up to one month we should be alert for ophthalmia neonatorum (ON), usually caused by gonorrhoea or chlamydia passed from the mother’s genital tract to the baby’s eye during birth. It isn’t common (UK incidence is three to seven per 100,000 live births) but should not be missed as it can lead to serious complications including permanent visual impairment.6 Suspect ON in a baby aged under one month who has red, swollen, watery eyes with a discharge. Refer for same-day review by an ophthalmologist, who will usually take swabs and treat while results are pending.9 Swabs may also be arranged for the baby’s mother. 

Key points

  • Nasolacrimal duct obstruction is common in babies but can be mistaken for conjunctivitis 
  •  In an otherwise well baby with ‘watery/sticky eye’, where the sclera is not red, parents can be reassured that nasolacrimal duct obstruction is the more likely cause and advised on simple home management
  • Be very cautious with signs of eye irritation in young babies under one month

Dr Toni Hazell is a GP in north London


  1.  The College of Optometrists. Nasolacrimal duct obstruction (nasolacrimal drainage dysfunction). 2021. Link 
  2.  Moorfields Eye Hospital NHS Foundation Trust. NLDO: Blocked tear ducts in babies. 2018. Link  
  3.  American Association for Pediatric Ophthalmology and Strabismus. Nasolacrimal duct obstruction. 2020. Link 
  4.  Abdu L, Bawahab N, Mohammed Hussain R et al. Prevalence and treatment outcome of nasolacrimal duct obstruction in Saudi children with Down Syndrome. Cureus 2020;12:e6672. Link
  5.  Sathiamoorthi S, Frank R, Mohney B. Incidence and clinical characteristics of congenital nasolacrimal duct obstruction. Br J Ophthalmol 2019;103:527-9. Link
  6.  NICE CKS. Conjunctivitis – infective. 2022. Link
  7.  UK Health Security Agency. Red or painful eye: S11 closed consultation draft. 2022. Link  
  8.  Children’s Health Queensland Hospital and Health Service. Blocked tear duct (nasolacrimal duct obstruction). Link 
  9.  The College of Optometrists. Ophthalmia neonatorum. 2021. Link  


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