Rare diseases · Sign or symptom

Downturned corners of mouth

Downturned corners of the mouth

HP:0002714

What it means

A morphological abnormality of the mouth in which the angle of the mouth is downturned. The oral commissures are positioned inferior to the midline labial fissure.

This finding should be assessed with the mouth closed, the lips in relaxed contact, and the face relaxed. The finding may be difficult to assess if the lower lip is enlarged. Previous terms for downturned corners of mouth included Carp mouth andFish mouth which are no longer recommended (pejorative terms).

Rare diseases that can present with this106

Very common80–99%

29

Common30–79%

42

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Downturned mouth · Downturned oral commisures

Downturned corners of mouth

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This page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.