Optic pharmacology Flashcards
the eye can suffer from
Infections
Scratches
Bruises
Dry eye
Abnormal growth of eyelashes that rub on the eye
Tumors
Diagnostic tests for the eye include:
Schirmer tear test
Phenol Red Thread
Fluorescein stain
Rose Bengal
Intraocular pressure measurement
Schirmer tear test:
measures the amount of tears produced by the lacrimal (tear) glands.
Phenol Red Thread
is another newer, way to accurately evaluate tear production may be more accurate than the schirmer tear test
Fluorescein stain
checks to see if the cornea is intact or has an ulcer
–Corneal ulcers must be treated promptly or the eye can rupture.
Rose Bengal
a stain used to detect corneal damage due to viruses or low tear production (dry eye).
Intraocular pressure measurement
taken with a tonometer -
often a topical anesthetic is often used for this test.
high pressure leads to blindness.
Preparing an eye for treatment/tests
Topical anesthetic drops can be used to numb an eye to check for and remove a foreign body from the eye.
Drops vs ointment
Drops are relatively easy to apply, but a large portion of the medication is removed by the tear reaction within a short time.
As much as 90% of the drop is on the face within two to three seconds after the animal blinks and tears up.
Although ointments are harder to apply, they last longer and often make treatment more effective.
Mydriatics
Used to dilate the pupils, for exams or treatment
Long-acting mydriatics such as atropine will keep the pupil dilated and away from the cornea while a corneal ulcer heals.
Cycloplegics help paralyze the ciliary muscle, which reduces pain in the eye
Miotics (pharmacology)
Used to constrict the pupils.
help treat glaucoma, because when the iris contracts, the aqueous humor can flow out more readily.
Bonus- don’t need to know this. The drug most frequently used for this purpose is topical pilocarpine, which can be irritating to the eye and cause vomiting, diarrhea, and salivation.
Intraocular pressure treatment
Can can controlled by
the use of miotics
decreasing the production of aqueous humor.
– Carbonic anhydrase inhibitors
–beta blockers
–In emergency situations, the administration of mannitol intravenously will lower eye pressures by acting as a diuretic and drawing water out of the eye.
Carbonic anhydrase inhibitors when given orally, can cause
General excitement
Panting (fast, heavy breathing)
Vomiting
Diarrhea
collagen shield
Will cover an eye ulcer. The shield is like a contact lens, but it will dissolve in a few days. It decreases pain by preventing the eyelid from rubbing on the ulcer.
Horses tend to get what eye issue? And how treated?
Fungal diseases on their cornea, which is often treated with topical antifungals
