Major Uses

Sertraline is a selective serotonin reuptake inhibitor (SSRI) antidepressant medication that works by blocking serotonin receptors in the brain. It is chemically unrelated to other types of antidepressants and is most commonly used to assist in behavior modification programs aimed at treating fear-based behaviors, aggression, anxiety, and compulsive behaviors in dogs. The drug is also used to treat excessive fearfulness, compulsive behaviors, urine marking, and aggression in cats.

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

Common Precautions

Side effects commonly associated with proper use of sertraline include tremors, poor appetite, and lethargy. Itchiness, diarrhea, vomiting, anxiety, panting, sleep disturbances, agitation, and dry skin are other possible adverse effects. Loss of appetite can be significant, but it is usually temporary. Rarely, sertraline may increase aggression in dogs. If this occurs, the medication should be stopped immediately and a veterinarian should be consulted.

Sertraline should be used cautiously in animals with a history of blood disorders or seizures. If seizures develop during treatment, the drug should be stopped and a veterinarian should be consulted. The drug should only be used if absolutely necessary in geriatric animals and in those with liver disease. It is not for use in pregnant or lactating animals.

Sertraline is known to interact with certain other medications and supplements, including central nervous system depressants, warfarin, digoxin, phenylbutazone, cisapride, diazepam, buspirone, tricyclic antidepressants, cimetidine, cyproheptadine, metoclopramide, and others. The drug should not be taken within 5 weeks of taking a monoamine oxidase inhibitor due to the potential for a severe or fatal reaction. It is important to disclose all medications and supplements being taken before beginning treatment with sertraline.

Sertraline should not be used in animals with a known allergy or hypersensitivity to the drug. Overdose of sertraline can be serious or fatal and may cause diarrhea, lethargy, fever, tremors, drooling, vomiting, muscle rigidity, agitation, increased heart rate, seizures, vocalization, and coma. Any known or suspected overdose should be reported to a veterinarian right away.


Sertraline should be stored in its original packaging, out of the reach of children and animals, and at room temperature. It should be kept away from light and heat.


Sertraline is available as tablets in strengths of 25 mg, 50 mg, and 100 mg. It is also available as an oral concentrate for dilution. In dogs, the typical dose of sertraline is 1.25 to 2.5 mg/lb (2.5 to 5.0 mg/kg) by mouth once daily. In cats, the typical dose is 0.5 to 2.0 mg/lb (1.0 to 4.0 mg/kg) by mouth once daily.

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.

If a dose of sertraline is missed, it should be administered as soon as possible. If it is almost time for the next dose, the missed dose should be skipped and the normal schedule resumed. Two doses of this medication should not be given at once.

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.