Symptoms normally appear in babies under one year of age and are characterized by an upward stare or gaze, with the eyes rolled back, while the chin is typically held low.
[1] Babies suffering from PTU may exhibit normal or slightly jerky side-to-side eye movement, nausea, irritability, frequent sleep, developmental and language delays, vertigo and loss of muscle tone.
[citation needed] The condition is generally regarded as having a benign outcome, in the sense that it improves, rather than worsens over time.
Carbonic anhydrase inhibition has been reported to work in a small series.
Videotaping a child both in and out of the upgaze state can be vital for reaching a diagnosis.