Major Uses

Timolol maleate is a non-selective beta-adrenergic receptor-blocking agent that is most commonly used in ophthalmic form in order to treat glaucoma. It is mostly used to prevent glaucoma, as it is not strong enough to fully treat the condition on its own.

Common Precautions

Timolol maleate should be used cautiously in cats with asthma because it may trigger an asthma attack. Animals with respiratory disease, congestive heart failure, or animals that are pregnant or lactating should be administered timolol maleate with caution. Complications may arise if administered to patients that are taking vitamins, supplements, or other medications.

Some negative side effects associated with timolol maleate include swelling, itching, redness, and other forms of eye irritation. It may also cause the patient's pupil to become smaller. Other negative side effects may include diarrhea, nausea, anorexia, insomnia, depression, hypotension, and edema.

Timolol maleate should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if any negative side effects occur or if an overdose is suspected. Some possible symptoms of an overdose can include headache, chest pain, slow heart beat, dizziness, and fainting.


Timolol maleate should be kept at room temperature in a tight, light resistant, childproof container. It should be stored where children and pets will not be able to reach it.


Timolol is only supplied in the form of an eye drop. A typical dose is one eye drop twice a day. In some cases, this can be upped to three times a day upon a veterinarian's recommendation. Should a dose be forgotten, it should be administered as soon as possible. If it is almost time for the subsequent dose, the missed dose should be skipped and the regular dosing schedule should continue. Two doses should not be administered at the same time, as an overdose may occur.

Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.