Related Experiment Video
Updated: Aug 12, 2026

Optimization of the Retinal Vein Occlusion Mouse Model to Limit Variability
Published on: August 6, 2021
Cardiovascular effects of topical ophthalmic 10% phenylephrine in dogs
I P Herring1, J D Jacobson, J P Pickett
1Department of Small Animal Clinical Sciences, VA-MD Regional College of Veterinary Medicine, Blacksburg, VA 24061-0442, USA. iherring@vt.edu
Objective:
To evaluate the effect of topical ophthalmic 10% phenylephrine on systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), pulse rate (PR) and electrocardiogram (ECG) in dogs.
Animals Studied:
Nine clinically normal dogs.
Procedure:
Arterial catheters were placed in the dorsal pedal artery of awake dogs and ECG leads were attached. After a 15-min acclimatization period, baseline PR, SAP, DAP and MAP were recorded every 5 min for 20 min. Two treatment groups (eight dogs each) were studied. Group I: one drop of phenylephrine was placed in each eye once. Group II: one drop of phenylephrine was placed in each eye three times at 5-min intervals. Following treatment, PR, SAP, DAP and MAP were recorded every 5 min for 90 min. The mixed procedure of the SAS system was used to perform a repeated measures analysis of variance to test for linear and quadratic trends across time.
Results:
Group I: There was a significant quadratic decrease in PR across time (P = 0.0051). Systolic arterial pressure increased linearly with time (P = 0.0002), MAP increased linearly with time (P = 0.0131), and DAP increased linearly with time (P = 0.0001). Group II: There was a significant quadratic decrease in PR across time (P = 0.0023). There was a significant quadratic increase in SAP (P = 0.0324), MAP (P = 0.0103) and DAP (P = 0.0131) across time.
Conclusions:
Topical ophthalmic application of 10% phenylephrine in normal dogs results in elevation of arterial blood pressure and reflex bradycardia.
Related Concept Videos
Direct-Acting Cholinergic Agonists: Therapeutic Uses
Adrenergic Agonists: Direct-Acting Agents
These agents can be classified...
Adrenergic Agonists: Therapeutic Uses
Emergency and Intensive Care Unit (ICU) applications: Pressor agents increase blood pressure, heart rate, and contractility in shock and organ failure situations. Dopamine can induce vasodilation and stimulate adrenoceptors. Endogenous catecholamines are effective in treating cardiogenic shock. α2-agonists like clonidine can reverse anesthesia-induced hypertension.
Allergies and anaphylaxis:...
Adrenergic Antagonists: Pharmacological Actions of β-Receptor Blockers
Open Angle Glaucoma: Treatment
Drugs such as carbonic anhydrase inhibitors, α2- and...
Ophthalmic Drug Delivery Systems

