Trazodone for Dogs: Uses, Benefits, and Precautions for Dog Behavior Management
Have you ever experienced a bout of anxiety in your dog? Maybe he became afraid and agitated during a thunderstorm, a road trip, or at the dog park. In these cases, your dog may feel out-of-control about the things and events happening around him.
Now, there’s one effective medication that veterinarians prescribe to manage anxiety in dogs. It’s called trazodone, and antidepressant medication in humans. Learn more about trazodone’s indications, dosage, benefits, and precautions in this article.
- What is Trazodone?
- Trazodone for Dogs Mechanism of Action
- What Does Trazodone Treat?
- Benefits of Trazodone for Dogs
- Trazodone for Dogs Dosage and Therapy Duration
- Side Effects of Trazodone for Dogs
- Serotonin Syndrome in Dogs
- Contraindications for Trazodone Use in Dogs
- Potential Drug Interactions with Trazodone
- Your Dog on Trazodone Therapy
What is Trazodone?
Trazodone is a human-approved medication used to treat major depressive disorder and anxiety disorders. It is also used in veterinary medicine as an off-label drug for canine anxiety disorders.
Trazodone is classified as a selective serotonin reuptake inhibitor (SSRI). It is also labeled as a serotonin antagonist and reuptake inhibitor (SARI). The drug primarily works to increase serotonin levels in the body. This mechanism helps diminish anxiety, promotes calmness, and improves energy levels, mood, and appetite.
Veterinarians typically prescribe trazodone for dogs for short-term relief of anxiety in dogs who:
- Are always uneasy
- Are encountering stressful situations or illnesses
- Just underwent an orthopedic surgery
The efficacy and safety of trazodone use in dogs have been undisputed for years. As with other human medications, it carries some side effects that are fortunately uncommon with proper veterinary guidance and ethical medication use.
Trazodone is available as a generic drug and is also sold under several brand names such as Oleptro and Desyrel. It’s available in small round tablets with varying strengths (25 mg, 50 mg, 100 mg, 150 mg, and 300 mg).
Trazodone for Dogs Mechanism of Action
Trazodone works by antagonizing two receptors: the 5-HT2A and the alpha-1 adrenergic receptor. When trazodone blocks these two receptors, the result is varying levels of sedation in dogs. This contributes to the calming effect of the medication.
Now, trazodone also selectively blocks serotonin reuptake. Serotonin is a hormone and neurotransmitter that influences pain perception, mood, appetite, and heart function – it functions the same way in both humans and dogs. Serotonin reuptake happens when serotonin gets reabsorbed by a brain cell after it has already transmitted a nerve impulse through a synapse.
Trazodone acts on the reuptake to prevent serotonin from being reabsorbed and thus increase its levels in the brain. The result is an increase in the effects of serotonin – calmer mood and lesser pain perception.
What Does Trazodone Treat?
Trazodone for dogs is used to manage several behavior-related conditions. This includes separation anxiety and stressful situations. Illness-induced anxiety and generalized anxiety common to certain breeds also come into play. Moreover, Trazodone may be used in conjunction with pain medications to manage a dog’s orthopedic surgery.
This refers to a condition where your dog suffers from physical and mental changes every time he gets separated from you. He becomes increasingly withdrawn when you leave because he feels uncomfortable being left alone. 
Physical changes related to separation anxiety include:
- Elevated blood pressure
- Fast pulse and heart rate
- A rise in body temperature
Meanwhile, behavioral changes during separation anxiety include:
- House soiling
- Destructive chewing
- Excessive licking
All these behavioral problems arise not because your dog wants to act out, but because he is anxious without you around him.
There are plenty of stressful situations that may become a source of behavioral problems and anxiety for your dog. These situations may seem mundane for humans, but it’s a different story for dogs.
For instance, a fireworks display may seem harmless, but to your dog, it will cause so much anxiety. That’s because dogs hear four times better than humans – their hearing ranges up to 45,000 Hertz while humans can only hear until 23,000 Hertz.  Hence, the loud crackling sounds of fireworks are heard by your dog four times louder, causing his anxiety and agitation. This goes the same for thunderstorms.
Your dog may also feel agitated and anxious during these situations:
- Car trips
- Veterinarian visits
- Meeting new people or animals (such as in a dog park)
A normally non-anxious dog may develop anxiety due to certain illnesses such as:
- Loss of vision or hearing
Your veterinarian will evaluate if trazodone is suitable for your dog experiencing illness-induced anxiety, based on his particular disease, symptoms, and medical history. Trazodone is typically allowed for short-term management of anxiety in these dogs.
Some dog breeds are more inclined to developing anxiety for unknown reasons. These include several toy breeds and the following dogs:
- Bichon Frise
- Cocker Spaniel
- Border Collie
- Labrador Retriever
- German and Australian Shepherd
- King Charles Spaniel
- Shorthair Pointer
It could be that these dogs simply get upset quickly once they detect a change in the environment or the people surrounding them. Generalized anxiety often goes unnoticed because of its subtleness. Some pet owners shrug off this anxiety as a normal breed characteristic when, in fact, it is already not normal behavior.
One retrospective study found out that trazodone is an effective medication for treating canine anxiety disorder. The drug was well-tolerated by 56 dogs when it was used in conjunction with other behavior-modifying medications.
Trazodone can be used to keep dogs calm after orthopedic surgery. Keeping dogs calm post-operatively allows them to heal faster and lessens potential complications from the surgery.
A 2014 study concluded that dogs displayed significant improvement when given oral trazodone for 4 weeks from the first day after their orthopedic procedures. Trazodone was given with tramadol for the first three days postop for pain management. After that, tramadol was discontinued and trazodone’s dose and interval were increased. More than 90% of the 36 dogs enrolled in the study reported satisfactory results in keeping the pain away and calming dogs during the critical recovery period after orthopedic surgery.
At times, veterinarians may also give small doses of intravenous trazodone as part of an anesthesia plan before surgery. It is given as a pre-medication together with opioid agents.
Benefits of Trazodone for Dogs
Trazodone may not be labeled as a veterinary-use drug, but it’s among the many human-approved drugs that can be safely administered to dogs. The main benefit of trazodone is its ability to effectively reduce anxiety and modulate a dog’s behavior without causing substantial side effects. Perhaps more clinical trials are needed to cement this, but the consensus of the veterinary world is clear – trazodone is currently a safe and effective drug, carries only mild side effects, and is well-tolerated by several dogs.
Apart from that, other known benefits of trazodone for dogs include the following:
- Does not cause changes in a dog’s cardiac condition
- Carries a low seizure risk than opioids
- No need to taper off after ending the therapy duration
- Easy to administer to dogs
- Cost-effective, especially with a generic tablet available (usually 2 cents or less per tablet)
Trazodone for Dogs Dosage and Therapy Duration
According to this review from the American Journal of Animal and Veterinary Sciences, trazodone has different dosage recommendations depending on the condition:
- As a daily treatment for anxiety – 1.9 to 16.5 mg/kg of body weight, given every 24 hours orally
- Anxiety treatment as needed only – 2.2 to 14 mg/kg of body weight, given orally as needed for general anxiety
- Before anticipated stressful events such as a vet visit or fireworks display – 4-12 mg/kg of body weight given 1 ½ hour before the stressful event occurs
- General and behavioral anxiety – 3-7 mg/kg of body weight, given orally either as a lone therapy or in combination with tramadol, NSAIDs, or other medications
- Before an operation – 5-7 mg/kg of body weight given 2 hours before surgery; may be used in combination with opioids
- After an operation, particularly orthopedic procedures – 3.5 mg/kg of body weight for 3 days combined with tramadol, then 7 mg/kg given orally every 12 hours 4-12 weeks following the orthopedic surgery
- After orthopedic operations on an as-needed basis – 7-10 mg/kg given every 8 hours orally as needed
These recommendations are highly specific, but your veterinarian will still be the one to determine the right dosage for your dog’s condition. He’ll typically start on the lowest possible dose depending on your pet’s condition to see if your dog will respond positively despite the low dose. Never attempt to calculate the dosage for your pet alone!
Side Effects of Trazodone for Dogs
Trazodone may cause any of the following side effects in dogs:
- Diarrhea and/or vomiting
- Aggression or increased anxiety
- Hyperactivity and restlessness
- Shuffling and unsteady gait (ataxia)
- Priapism (painful and persistent penile erection)
- Aggressive food-seeking
Most veterinarians use the lowest possible trazodone dose to detect any potential side effects and acclimate the dog to milder effects like gastric upset and diarrhea. Low doses often work well in dogs and help prevent bouts of side effects.
Serotonin Syndrome in Dogs
The most serious side effect of trazodone in dogs is called serotonin syndrome. It is a group of symptoms that appear as a reaction to excessive serotonin levels in the brain.
Remember that trazodone’s mechanism of action balances serotonin levels in the brain. But too much use of trazodone can flood the brain with serotonin and cause the following symptoms:
- Altered mental status
- Constant diarrhea
- Fast heart rate
- Elevated blood pressure
- Increased reflexes
- Involuntary muscle jerking (myoclonus)
- Dilated pupils
- Excessive salivation
- Difficulty in breathing
Taking trazodone together with other drugs such as antidepressants (MAOIs, TCAs, SSRIs), opioids, 5-HT1 agonists, CNS stimulants, and psychedelics increase the risk of serotonin syndrome. Some herbs may also cause this side effect.
Serotonin syndrome’s symptoms usually start rapidly upon the build-up of extra serotonin. Stop giving trazodone and bring your dog to the veterinarian immediately if you see at least three of the symptoms listed here. Your dog will likely be given cyproheptadine, a serotonin antagonist medication used to alleviate the syndrome and bring back serotonin levels in the brain to normal.
Serotonin syndrome is highly unlikely in dogs using vet-controlled doses of trazodone. However, it’s best to arm yourself with this information in case of an overdose or drug interaction.
Contraindications for Trazodone Use in Dogs
Trazodone should not be given to dogs who:
- Are taking MAOI drugs like amitraz and selegiline (medications for tick control)
- Have hypersensitivity to trazodone or similar drugs
- Has problems with the kidneys, liver, and heart
- Suffers from angle-closure glaucoma
- Are pregnant or lactating
Your veterinarian will consider the risks versus benefits of giving trazodone depending on your dog’s condition.
Potential Drug Interactions with Trazodone
As we detailed in the previous sections, trazodone may interact with certain medication groups and cause serotonin syndrome. Notable drug classes that cause serotonin syndrome together with trazodone include monoamine oxidase inhibitors (MAOIs), phenothiazines, fluoxetine, tramadol, CNS depressants, and SSRIs.
Other drugs that cause interactions with trazodone include:
- Azole antifungals (itraconazole, fluconazole, etc.)
- Fluoroquinolones (ciprofloxacin, ofloxacin)
- Diuretics (thiazide, loop, and potassium-sparing diuretics)
- Macrolide antibiotics (erythromycin, clarithromycin, etc.)
Some herbs may also interact with trazodone. St. John’s Wort and Panax Ginseng typically cause serotonin syndrome or other potential problems.
Disclose to your dog’s veterinarian any medications, herbal remedies, and supplements your pooch is taking, whether it be over-the-counter or prescription.
Your Dog on Trazodone Therapy
How do you take care of your dog on trazodone therapy? Here are a few tips:
- You may give trazodone with or without food. However, many dog parents give it food to prevent stomach problems. Giving the tablets with food or a small treat will also make it more palatable; your dog will not likely throw it up due to an unpleasant taste.
- Do not give double doses when you accidentally skip a dose. Just resume the regimen at the next scheduled dose. Giving another dose to make up for a missed one may induce an overdose and potentially serotonin syndrome.
- Soothe your dog every time he takes trazodone. Remember that the medication is meant to ease anxiety, so you can also provide your dog with soothing activities such as a tummy rub or massage.
- For behavioral anxiety, your vet will likely pair up trazodone therapy with a behavioral modification program. Gentle and consistent support in both therapies will help tame any destructive behavior arising from anxiety.
- Trazodone may be prescribed to calm your active dog after surgery. Help him calm down by providing a confined and quiet space to stay. Distract him by placing treats inside a Kong toy for him to discover on his own. You may also play gentle mind games such as cup games, puzzle games, and stimulating smells.
Trazodone is a safe and effective medication used off-label for anxious dogs. Pre-operative and post-operative dogs are also given trazodone to calm their nerves and help them relax. The medication has few side effects as well.
Your veterinarian will work with you to determine the best dose and the right way to care for your dog on trazodone therapy. But armed with all the information on this article, you’ll be well on your way to caring for your anxious dog properly while taking trazodone.
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