MSD Manual

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MSD Manual
Veterinary Manual
The trusted provider of veterinary information since 1955

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VETERINARY PET
Grass sickness after eye drops, horse
dysautonomia-grass-sickness-horse-eye-hahn-high
Grass sickness after eye drops, horse

    Grass sickness case 20 minutes after administration of 0.5% phenylephrine eye drops into the right eye. Note the change in angle of the eyelashes in relation to the head.

Courtesy of Dr. Caroline Hahn.

In these topics
Equine Dysautonomia

Merck & Co., Inc., Rahway, NJ, USA (known as MSD outside of the US and Canada) is dedicated to using leading-edge science to save and improve lives around the world.  The Veterinary Manual was first published in 1955 as a service to the community.  The legacy of this great resource continues in the online and mobile app versions today.

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