Common Psychotropic Medications

Medications that have been used to treat behaviour problems include the benzodiazepines, tricyclic antidepressants (TCAs), antihistamines, azapirones, selective serotonin reuptake inhibitors (SSRIs), serotonin antagonist reuptake inhibitors (SARIs), and beta blockers. Additionally, synthetic pheromone analogues play an important role in managing behaviour problems in pets.

Tricyclic Antidepressants (TCA)

Clinical Uses

 Cats: Spraying, FLUTD, over-grooming, anxiety, intercat aggression, obsessive-compulsive disorders

 Dogs: Impulse control aggression, fear aggression, separation anxiety, obsessive-compulsive disorders, acral lick granulomas, fears and phobias such as thunderstorm phobia

Side Effects

Short-term lethargy or sedation, mild and intermittent vomiting (usually transient) and increases or decreases in appetite, dry mouth, constipation, urinary retention, tachycardia, cardiac arrhythmia and decreased tear production.

Contraindications

High doses have been associated with increased liver enzymes, hepatotoxicity and convulsions. They should not be used in cases with cardiac dysrhythmia, urinary retention, narrow angle glaucoma, seizures or within 2 weeks of MAOI administration. These medications may also interfere with thyroid medications and should be used with caution in these patients.

Examples

Amitriptyline

 Cats
0.5–1.0 mg/kg PO SID

 Dogs
1–3 mg/kg PO SID–BID

Clomipramine

 Cats
0.25–0.5 mg/kg PO SID

 Dogs
1–2 mg/kg PO BID 2 weeks, then 3 mg/kg PO BID if needed

Doxepin

 Cats
0.5–1.0 mg/kg PO SID–BID

 Dogs
3–5 mg/kg PO BID (for acral lick dermatitis)

Selective Serotonin Reuptake Inhibitors (SSRI)

As the name implies, they are selective for serotonin and lack the anticholinergic and cardiovascular side effects of the TCAs.

Clinical Uses

 Cats: Spraying, anxiety disorders, some types of aggression, obsessive-compulsive disorders

 Dogs: Obsessive-compulsive disorders, separation anxiety, generalised anxiety or global fear, some types of aggression

Side Effects

Reported side effects include liver changes, GI disturbances and rashes while nausea, lethargy, weight loss, tremors, agitation have been reported in people.

Contraindications

They should not be used concomitantly with MAOIs (serotonin syndrome) and at least 2 weeks should be allowed as a washout period between SSRI and MAOI therapy, 5 weeks for fluoxetine.

Examples

Fluoxetine

 Cats
0.5 mg/kg PO SID–BID

 Dogs
1 mg/kg PO SID

Paroxetine

 Cats
0.5–1 mg/kg PO SID

 Dogs
0.5–2 mg/kg PO SID

Sertraline

 Cats
0.5–1.5 mg/kg PO SID

 Dogs
1–3 mg/kg PO SID

Serotonin Antagonist Reuptake Inhibitor (SARI)

Trazadone is a serotonin 2A antagonist reuptake inhibitor (SARI) that blocks postsynaptic serotonin 5-HT and alpha-adrenergic receptors. Trazodone hydrochloride is an antidepressant chemically unrelated to tricyclic, tetracyclic, or other known antidepressant agents. It is used in human medicine as an antidepressant, anti-obsessional and antianxiety agent.

Clinical Uses

 Cats: Anxiety disorders

 Dogs: As an adjunctive agent in combination with selective serotonin reuptake inhibitors (SSRI) or tricyclic antidepressants (TCA) for anxiety, obsessive-compulsive disorders, separation anxiety, generalised anxiety or global fear, some types of aggression; can be used as a standalone medication in some cases

Side Effects

Reported side effects in dogs include vomiting, gagging, colitis, increased excitement, sedation, increased appetite and perceived behavioural disinhibition.

Contraindications

Trazodone is contraindicated in patients with known hypersensitivity to trazodone

Examples

Trazodone

 Cats
1–2 mg/kg PO BID

 Dogs
3–7 mg/kg PO BID or PRN

Synthetic Pheromone Analogues

Clinical Uses

 Cats: Urine spraying, anxiety, helping tolerate clinical examinations during a veterinary consultation, calm before travel, familiarisation with new houses or cattery environments, stimulating appetite in hospitalised cats; it has also been reported to help control undesirable scratching behaviour

 Dogs: Help stop or prevent fear and stress-related signs in puppies and adult dogs, helps with attention seeking behaviours and excessive licking (adult dogs), destructiveness, vocalisation and learning (puppies)

Side Effects

None have been reported, although some clients claim that the vehicle is irritating. Take caution with birds in the environment.

Examples

Feliway

Spray daily at a height of 20 cm (cat nose level) in 6–8 prominent locations per room - including areas that have been marked with urine. Needs to be used continuously 21 days for scratching, 30 days for urine marking, 45 days for older cats.

For travel, spray cat carrier 15 minutes prior to introducing the cat.

The plug-in diffuser should be placed in the room that the cat spends most of its time. It needs to be used continuously for at least 30–60 days.

Adaptil (Dog-Appeasing Pheromone)

Plug the diffuser into the room most commonly used by the dog. It needs to be used continuously for at least 30–60 days. Spray onto bandana or in crate/car before travel. Collar needs to be placed snugly around the dog's neck and should be replaced every 30 days

References

1.  Crowell-Davis SL, Seibert LM, Sung W, et al. Use of clomipramine, alprazolam and behavior modification for the treatment of storm phobias in dogs. J Am Vet Med Assoc. 2003;222:744–748.

2.  Denenberg S, Landsberg GM. Effect of dog-appeasing pheromones on anxiety and fear in puppies during training its effects on long-term socialization. J Am Vet Med Assoc. 2008;233:1874–1882.

3.  Gruen ME, Sherman BL. Use of trazodone as an adjunctive agent in the treatment of canine anxiety disorders: 56 cases (1995–2007). J Am Vet Med Assoc. 2008;233(12):1–6.

4.  Landsberg G, Hunthausen W, Ackerman L. Handbook of Behaviour Problems of the Dog and Cat. Oxford, UK: Butterworth-Heinemann; 2007.

5.  Overall KL. Clinical Behavioral Medicine for Small Animals. St Louis, MO: Mosby; 1997.

6.  Perrin C, Seksel K, G. Drug dosage chart. In: Lansberg G, Tynes V, eds. Behavior: A Guide for Practitioners. Veterinary Clinics of North America: Small Animal Practice; May 2014:629–632.

7.  Rang HP, Dale MM, Ritter JM, Gardner P. Pharmacology. New York, NY: Churchill Livingstone; 1995.

8.  Seksel, K. In: Maddison J, Page S, Church D, eds. Small Animal Clinical Pharmacology. 2nd ed. London, UK: WB Saunders; 2008:126–147.