What Does Constricted Pupils Mean?
Constricted pupils refers to the involuntary reflex in which the pupils narrow to regulate the amount of light exposure that enters the eye. The parasympathetic nervous system in the brain autonomously constricts the pupils in response to various external stimuli. In addition to natural and artificial light sources, ingestion of prescribed medications or illicit substances can cause constricted pupils. In some cases, pupils unable to constrict normally can indicate a pathological condition leading to serious visual impairment.
WorkplaceTesting Explains Constricted Pupils
While there are a wide variety of medical conditions that can cause constricted pupils, it is also a sign of drug use (specifically opiods) in some cases. Some non-opiate medications can also cause constricted pupils. Medications such as antidepressants and drugs used to treat hypertension (high blood pressure) have been known to cause constricted pupils.
Constricted pupils can serve as a preliminary warning of suspected drug use during pre-employment, random, and post-incident drug screen testing. However, constricted pupils alone are not enough to prove drug use because of the wide variety of underlying issues that could cause constricted pupils.