mydriasis

Etiology

• widening or dilation of the pupils, secondary to:
  • a physiologic response to dim light
  • a pharmacologic response to mydriatic agents*
  • injury to the eye

* sympathomimetics as a general class induce mydriasis

• amphetamines & other adrenergic neuron stimulants
  • cocaine
  • serotonin syndrome

Mydriasis is controlled by sympathetic innervation from the superior cervical ganglion & relaxation of parasympathetic tone from the oculomotor nerve.

See also miosis (contraction of the pupil).

More general terms

• sign/symptom

Additional terms

• mydriatic agent