Related Experiment Video
Updated: Jun 10, 2026
Pupillary Response as Assessment of Effective Seizure Induction by Electroconvulsive Therapy
Published on: April 11, 2019
[Infrared pupilometry as a biomarker of drug effects]
Olga Matousková1, Ondrej Slanar, Lukás Chytil
1Univerzita Karlova v Praze, 1. lékarská fakulta, Farmakologický ústav, Oddelení klinické farmakologie. olga.matouskova@lf1.cuni.cz
Background:
Measurement of the size of the pupil is used as a biomarker of drug efficacy, assessing mainly their effect on the central nervous system. The aim of our study was to evaluate sensitivity of various pupilometric parameters as biomarkers of widely used opioid analgesic drug tramadol.
Methods And Results:
Pharmacodynamic action of tramadol drops given orally in standardized dose of 0.7 mg/kg was studied in 60 healthy volunteers. Commercially available infrared pupilometer Pupilscan II was used for the measurements of static and dynamic pupilometric parameters prior the dosing and 2.5 hours afterwards. Drug-induced decreases of the initial diameter (0.49 mm) and final diameter (0.38 mm) were significant in the right eye, as well as in the left eye. Minimal parameters (0.35 mm) and time to minimum (0.03 mm) were significantly lower after tramadol administration in the left and right eye only.
Conclusions:
Our results confirm the use of pupilometry as an objective, non-invasive tool for evaluation of pharmacodynamic activity of drugs.
More Related Videos
07:26Assessing Pupil-linked Changes in Locus Coeruleus-mediated Arousal Elicited by Trigeminal Stimulation
Published on: November 26, 2019
06:04Objective Nociceptive Assessment in Ventilated ICU Patients: A Feasibility Study Using Pupillometry and the Nociceptive Flexion Reflex
Published on: July 4, 2018
