Overview of Tropicamide Ophthalmic Solution for Dogs and Cats

Tropicamide, commonly known as Tropicacyl®, is a drug used to dilate the pupils for short periods of time, usually during eye examinations in dogs and cats.

Tropicamide acts on the parasympathetic nervous system.

It is rapidly absorbed into the eye and produces dilation of the pupil within 15 to 30 minutes. The drug does not bind to tissue as strongly as atropine, so the dilation is short-lived and there are few residual effects. Duration of the pupil dilation (mydriasis) in normal eyes is usually only 3 to 6 hours, although occasionally the effect may last up to 12 hours.

Tropicamide belongs to a class of drugs known as cycloplegic mydriatics. These drugs dilate the pupil and temporarily paralyze the iris sphincter muscle that controls pupil movement.

Tropicamide is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.

This drug is not approved for use in animals by the Food and Drug Administration, but it is prescribed legally by veterinarians as an extras-label drug.

Brand Names and Other Names of Tropicamide

This drug is registered for use in humans only.

Human formulations: Tropicacyl® (Akorn), Tropicamide sterile ophthalmic solution® (Medical Ophthalmics), Tropicamide ophthalmic solution® (Bausch & Lomb), and various generic preparations
Veterinary formulations: None

Uses of Tropicamide for Dogs and Cats

Tropicamide is used to induce mydriasis to help in the examination of the lens and retina of the eye.

Tropicamide is occasionally used in treatment when short-acting pupil dilation is desirable, such as before and after cataract surgery.

It may also be used to induce mydriasis in cases where a concern exists that intraocular pressures may become elevated with the use of other mydriatic agents.

Precautions and Side Effects

While generally safe and effective when prescribed by a veterinarian, tropicamide can cause side effects in some animals.

Tropicamide should not be used in animals with known hypersensitivity or allergy to the drug.

Tropicamide does not produce higher intraocular pressure (IOP) in normal dogs, but has briefly increased IOP in people with glaucoma.

The glaucoma-inducing properties of tropicamide are less than those of atropine, but the drug should be used with caution in any animal prone to glaucoma. If possible, its use should be avoided in animals diagnosed with overt glaucoma.

Administration of topical tropicamide may produce salivation, especially in cats.

There are no documented adverse drug interactions associated with the use of these agents topically.

How Tropicamide Is Supplied

Tropicamide is available as 0.5% and 1% solutions in 12 or 15 ml bottles.

Dosing Information of Tropicamide for Dogs and Cats

Medication should never be administered without first consulting your veterinarian.

One drop of tropicamide may be sufficient to induce mydriasis in normal eyes within 30 minutes in dogs and cats.

When used in treatment of (and not to diagnose) an eye condition, the drug is administered 1 to 4 times daily depending upon the desired amount of mydriasis to be produced and the responsiveness of the eye to the drug.

The duration of administration depends on the condition being treated, response to the medication, and the development of any adverse effects.