Tropicamide - Ophthalmic

By Rania Gollakner, BS, DVM, MPH

What is tropicamide?

Tropicamide ophthalmic (brand names: Mydriacyl®, Paremyd®) is an anticholinergic eye medication used to dilate the pupils of the eye. This is particularly useful for examining the back of the eye and for preventing scar tissue formation after cataract surgery. It also has mild paralytic effects on the ciliary muscle in the eye.

Its use in cats, dogs, horses, and other species to dilate the eyes and prevent scar tissue after cataract surgery is ‘off label’ or ‘extra label’. Many drugs are commonly prescribed for off label use in veterinary medicine. In these instances, follow your veterinarian’s directions and cautions very carefully as their directions may be significantly different from those on the label.

How is tropicamide ophthalmic given?

Tropicamide ophthalmic is administered to the eye in the form of a liquid or ointment. Do not touch the tip of the bottle to the surface of the eye during administration. Wash hands before and after giving the medication. Wait 5-10 minutes after applying this medication before applying other eye medications. Do not give this to your pet if the medication is cloudy.

This medication will take effect quickly, in about 1 to 2 hours, and improvement in clinical signs should follow.

What if I miss giving my pet the medication?

If you miss a dose, give it when you remember, but if it is close to the time for the next dose, skip the dose you missed and give it at the next scheduled time, and return to the regular dosing schedule. Never give your pet two doses at once or give extra doses.

Are there any potential side effects?

Side effects include drooling, eye dryness, temporary stinging sensation upon initial application to the eye, light sensitivity, and blurry vision. Serious side effects include rash, itching, swelling, trouble breathing, painful eyes characterized by squinting and eye-rubbing, or a racing heart rate. Side effects in people include dry mouth, increased heart rate, headache, nausea, vomiting, abnormal behavior, and tense muscles: the significance of these side effects in animals is unknown at this time.

This short-acting medication should stop working within 24 hours.

Are there any risk factors for this medication?

Tropicamide should not be used in pets that are allergic to it or in pets with glaucoma. It should be used cautiously in pets that are pregnant or nursing, or in horses with colic.

Are there any drug interactions I should be aware of?

There are no specific drug interactions with tropicamide. Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking.

Is there any monitoring that needs to be done with this medication?

There is no specific monitoring that needs to be done while your pet is taking this medication. Your veterinarian may monitor your pet to be sure that the medication is working. Monitor your pet at home for serious side effects.

How do I store tropicamide?

Store this medication at room temperature and protect from freezing, moisture, and direct sunlight.

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility.

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