When the average individual hears epinephrine they likely think about energy pills and drinks that were summarily banned in the past decade. While epinephrine abuse has an unfortunate history, epinephrine ophthalmic has been utilized for a very long time to benefit eye patients. Continue reading to learn more about epinephrine ophthalmic history, its uses, and potential side effects.
Epinephrine is more commonly known as adrenaline. It is a hormone that is secreted by the adrenal glands and certain neurons. In addition to playing a key part in our body’s fight-or-flight response, it has been utilized in a myriad of medical applications, including anaphylaxis shock, cardiac arrest, asthma, and eye care.
After Kokichi Takamine first isolated epinephrine in 1901, it didn’t take long for it to be experimented medically. Cocaine-based local anesthesia was the first experiment. It was documented for its potential medicinal purposes since the 17th century. After being used in local anesthesia for ophthalmology in 1884 by Dr. Karl Koller, it continued to remain popular into the beginning of the 20th century.
With the isolation of epinephrine, a combination of cocaine and epinephrine was used to improve the blocking of pain signals in the optic nerve during eye surgery. Adding epinephrine extended the local anesthesia duration, making surgery completion easier. It also decreased vitreous pressure, decreased bleeding, and reduced the amount of cocaine needed for surgery but side effects such as cold sweats, hallucinations, and increased heart rates persisted.
By 1905, procaine (novocain) had been created, replacing most medical purposes for cocaine. Epinephrine was still utilized in very small doses with procaine, but side effects lingered here as well. In the past sixty years, more effective local anesthetics have been created, such as proparacaine and lidocaine.
Today, epinephrine is often mixed with lidocaine to aid in cataract surgery and other eye surgeries.
Researchers have found new uses for epinephrine in eye care, especially for glaucoma.
Epinephrine-class drugs reduce the amount of fluid in the eye, which is particularly beneficial in reducing pressure. Since glaucoma gradually increases pressure in the eye – to the point of damaging the optic nerve, causing vision loss – epinephrine is an effective option for preventing damage. Studies conducted by Dr. PF Hoyng and Dr. CL Dake in the 1980s showed that one version of epinephrine eye drops could reduce pressure by 44%. Since then, more modern eye drops such as Propine have continued to be effective while minimizing side effects.
While epinephrine ophthalmic has shown to be helpful with open-angle glaucoma, it is not ideal for narrow-angle glaucoma.
Epinephrine’s pharmacology in modern topical eye treatments has been largely refined to the point where side effects aren’t common, however, there are side effects that individuals may encounter. Some include mild to severe stinging or burning sensations, blurred vision, increased heart rate, headaches, higher blood pressure, and watery eyes.
One of the rarer side effects from prolonged epinephrine eye drop use is the buildup of adrenochrome deposits in the eye. Adrenochrome is synthesized when epinephrine oxidizes. It is also sold on its own in supplements, however in a controlled fashion by the FDA.
Over time, the adrenochrome may appear as crystallized pigments in the conjunctiva, iris, lens, and retina. If adrenochrome deposits become highly apparent, alternative treatment may be necessary. Consult your doctor about other glaucoma procedures.
At Marano Eye Care, we are dedicated to keeping our patients properly informed, no matter how big or small the details are. If you have any questions about eye symptoms, existing eye conditions, or need a complete eye exam, contact us today.
