What are the potential complications of HFMD that I should be aware of in my practice?

Guideline-aligned answer with reasoning, red flags and references. Clinically reviewed by Dr Kola Tytler MBBS CertHE MBA MRCGP.

Posted: 16 August 2025Updated: 16 August 2025 Guideline-Aligned (High Confidence) Clinically Reviewed
Dr Kola Tytler MBBS CertHE MBA MRCGPClinical Lead • iatroX

Potential complications of hand, foot, and mouth disease (HFMD) to be aware of in general practice include:

  • Central nervous system involvement such as encephalitis, which may present with persistent or severe headache, myoclonus with sleep disturbances, confusion, weakness, lethargy, drowsiness, irritability, generalized seizures, and coma. These signs require urgent hospital admission.
  • Significant dehydration, especially in young children, indicated by reduced urine output, lethargy, cold peripheries, and reduced skin turgor, which may necessitate hospital admission.
  • Persistent oral ulcers lasting more than 3 weeks, which may require referral via the 2-week wait pathway to exclude other causes such as malignancy.
  • Secondary bacterial skin infection, although antibiotics should only be prescribed if such secondary infection is suspected.
  • In pregnant women, although no clear evidence links HFMD to fetal risks, there is a rare risk of neonatal infection if the mother is infected near delivery, which may lead to severe neonatal illness or death, warranting specialist advice and possible neonatal observation.

Routine follow-up is not usually required unless complications develop or symptoms persist.

Antiviral medications are not recommended as they are not effective against the enteroviruses causing HFMD.

Good hygiene and supportive care are essential to reduce transmission and manage symptoms.

In summary, the main complications to monitor for are neurological involvement, dehydration, persistent oral ulcers, secondary bacterial infection, and rare neonatal complications in maternal infection near delivery.

Educational content only. Always verify information and use clinical judgement.