Zoloft for Dogs: This Medication Can Help Dogs With Behavior Problems

Behavioral problems are a common complaint for many dog owners. Canine behavioral issues are often treated with a combination of training and medication. Medication helps your pup succeed at training and behavior change.

Selective serotonin reuptake inhibitors (SSRIs) are one type of medication prescribed to help dogs with behavioral issues. There are several SSRIs available for dogs, including Zoloft (sertraline). 

Here, we’ll discuss how Zoloft works for dogs, common side effects, dosages for dogs, and more. 

Zoloft for dogs at a glance

What is Zoloft for dogs, and what is it used for?

Zoloft can help treat several conditions and behavioral problems in dogs, including:

• Anxiety

• Phobias, such as fear of fireworks or thunderstorms

• Aggression

• Humping

• Urine marking 

• Compulsive disorders

As with all behavioral problems in dogs, medications like Zoloft are more successful when paired with training. Zoloft can help lower your dog’s anxiety to make training easier. Then, if training is successful for your dog, they may not need to stay on Zoloft long term. This isn’t always possible, but it is always the goal. 

Zoloft is prescribed off-label to dogs, meaning it’s not FDA approved for dogs. Off-label prescribing is common in veterinary medicine, and it’s safe for dogs. 

How does Zoloft work for dogs?

Zoloft for dogs contains sertraline. Sertraline is a selective serotonin reuptake inhibitor (SSRI) antidepressant. SSRIs work by increasing the amount of serotonin in the brain. It does so by preventing serotonin from being reabsorbed by brain cells, making more serotonin available. 

Serotonin is a neurotransmitter that helps regulate and improve mood. Because of this, SSRIs can help treat behavioral, mood, and compulsive disorders in dogs. 

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What is the dosage of Zoloft for dogs, and how is it given?

The dosage of Zoloft for dogs depends on what condition you’re treating. It also depends on your dog’s weight. But in general, Zoloft is given once a day. The dosage ranges from 1 mg to 3 mg per kilogram of body weight. 

Most veterinarians will start dogs on a lower dosage and increase as needed to manage your dog’s symptoms. The goal is to use the lowest dosage possible. It does take up to 30 days or longer for the medication to take full effect in your dog’s system.

You can pick up a Zoloft prescription either from human pharmacies or compounding veterinary pharmacies. It comes as a tablet or liquid to be given by mouth. 

Zoloft can be given with or without food. If your dog experiences an upset stomach or vomiting when they take the medication, try giving the medication with food or a treat.

Do you need to wean your dog off of Zoloft?

Yes, you should never abruptly stop giving a dog Zoloft. Doing so can cause withdrawal symptoms, including: 

• Sudden mood changes

• Increased aggression

• Vomiting

• Loss of appetite

• Lethargy 

If your dog needs to stop Zoloft, your veterinarian will give you a schedule to taper the medication to avoid withdrawal symptoms. Zoloft is a moderate-acting medication and should stop working within a few days of ending treatment. But it may take longer in dogs with liver or kidney disease.

What should you do if your dog misses a dose of Zoloft?

If you miss giving your dog a dose of Zoloft, give the next dose as soon as you remember. If it is within a few hours of when the next dose is scheduled, skip the missed dose. Then give the next dose at your dog’s regularly scheduled time. Never double up on doses to catch up, as this can risk a serious overdose.

What are the common side effects of Zoloft for dogs?

Zoloft for dogs can cause side effects, including:

• Vomiting

• Diarrhea

• Tremors

• Changes in sleep patterns

• Decreased appetite

• Increased anxiety

• Panting

• Sedation

If you notice that your dog is experiencing side effects after starting Zoloft, talk to your veterinarian as soon as possible for guidance.

What are the most serious risks of Zoloft for dogs?

The most serious Zoloft side effects in dogs are associated with serotonin syndrome. Serotonin syndrome happens when your dog has too much serotonin in their brain. 

Signs of serotonin syndrome in dogs include: 

• Tremors or twitching

• Seizures

• Hyperactivity, agitation, or restlessness

• Increased body temperature

• Fast heart rate

• Dilated pupils

• Confusion or abnormal behavior

• Inability to sleep

• Aggression

• Coma

If you suspect your dog has serotonin syndrome, take them to the veterinarian or emergency clinic for treatment immediately. This condition is an emergency.

Which dogs shouldn’t take Zoloft?

In certain situations, it might not be safe to give your dog Zoloft. Check with your veterinarian if your dog has any of the following conditions:

• Glaucoma

• Heart disease

• Bleeding disorders

• Seizures

• High blood pressure

• Liver disease

• Kidney disease

• Electrolyte issues

• Thyroid disease, such as hypothyroidism

• A history of allergic reactions to SSRIs

Depending on your dog’s health history, your veterinarian may decide it’s OK to give your dog Zoloft under their direct supervision.

Does Zoloft interact with other dog medications?

Yes, Zoloft can interact with many other medications your dog may be taking. Medications Zoloft interacts with include:

• Amitraz

• Azole antifungals, such as fluconazole or itraconazole

• Chlorpheniramine and other antihistamines

• Cisapride

• Diuretics

• Flea collars, such as Seresto

• Heart medications

• MAO inhibitors

• Mirtazapine

• NSAIDs, like carprofen

• Opioids

• Other SSRIs or antidepressants

• Sedatives

• Seizure medications, including phenobarbital and levetiracetam (Keppra)

• Tramadol

Why trust our experts?

Written by:

Sarah J. Wooten, DVM, CVJ

Dr. Sarah Wooten, DVM, CVJ, is a well-known international influencer in the veterinary and animal healthcare spaces. She has 16 years of experience in private practice and more than 15 years experience in veterinary media work.

Edited by:

Renée Fabian, MA

Renée Fabian is the senior pet health editor at GoodRx. She’s worked for nearly 10 years as a journalist and editor across a wide range of health and well-being topics.

Reviewed by:

Ghanasyam Bey, DVM

Ghanasyam Bey, DVM, is from Cleveland, Ohio, and attended Princeton University for undergraduate studies. After a year of biology research at Duke University, he attended Ohio State College of Veterinary Medicine.

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