Medical management considerations for separation anxiety

Photo: adogslifephoto

Separation anxiety is a common condition managed by small animal veterinarians that is typically treated with a combination of behavior modification and pharmaceuticals. Several medications are available for treating this condition, and veterinarians should create a customized plan based on each patient’s individual needs. In a continuing education session at the 2025 Fetch dvm260 Conference in Charlotte, North Carolina, Christopher Pachel, DVM, DACVM, CABC (IAABC), of the Animal Behavior Clinic in Portland, Oregon, shared his tips for identifying which patients need treatment and how to choose the appropriate medications.¹

Diagnosing separation anxiety

Before prescribing medication, the diagnosis of separation anxiety should be confirmed. Some pets can have problematic behaviors that occur while the owners are away that are not caused by anxiety. In making the diagnosis, Pachel stated “video is not optional. It is absolutely required.” Reviewing videos of the patient at home confirms the diagnosis based on the observed behaviors and provides objective data that can be used for tracking response to treatment, including latency between owner departure and problematic behavior, the frequency of the behavior, and the pitch of vocalization.

When deciding what medication is best, it is important to consider where and when problematic behaviors occur. From a patient’s perspective, life can be broken into 4 parts:

• Owner present
• Owner initiates a departure routine
• Isolation/separation from owner
• Owner returns (greeting)

Patients may exhibit problematic behaviors at a single point or multiple times during this cycle.

Asking specific history questions will help to identify “the support your patient actually needs,” said Pachel. Important information to collect from owners include the following:

• Are there other fear, anxiety, or arousal/reactivity issues that we also need to treat?
• How feasible is it to medicate the patient?
• Is there advanced notice of the owner’s departure for the pet?
• Is the owner’s departure schedule predictable and routine?
• What behaviors are occurring?
• How exuberant is the pet when the owner returns?
• How long does the enthusiastic greeting last before the pet returns to baseline?
• How has the pet responded to behavior modification in the past?

Pachel noted that “you won’t always have time to get all these details,” but it is helpful to have this information to pick the best possible medication from the job that is needed. Pachel suggested using a printed questionnaire to collect as much information as possible.

Choosing the right medication

Ultimately, the first choice that needs to be made is whether a maintenance, situational, or adjunctive medication is needed. In some cases, medications may need to be combined from different categories to achieve the desired treatment goal.

Maintenance medications are typically needed when departures are frequent, unavoidable, or unpredictable. Additional reasons to select maintenance medication include having a concurrent diagnosis that may benefit from medication use or when consistent medication administration is easiest for the owner. These medications have a long time to onset, which can be anywhere from 1 to 6 weeks depending on the medication. It is essential to set appropriate expectations on efficacy for the owner.

Situational medications are best for predictable, infrequent, avoidable departures that have a window of lead-up time to allow for onset of action. These medications have a much faster onset of action, usually 15 minutes to 2 hours. However, they do not work as well for daily use due to their short half-life.

“We don’t always have to reach for pharmaceuticals,” Pachel said. There are numerous supplements that can be considered as well, particularly in mild cases. Gabapentin is also used as an adjunctive treatment, but Pachel does not recommend using it as a sole agent.

Maintenance medication options

Multiple classes of medications are available for separation anxiety treatment, including selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, and serotonin norepinephrine reuptake inhibitor (SNRI). Two FDA-approved drugs are available for separation anxiety in dogs. “If you have an FDA-approved strategy, you usually start there,” Pachel said, “but there are a lot of good reasons that these may not be the best medication” for an individual pet.

SSRIs have extensive anecdotal experience behind their use and are effective for fear and anxiety as well as impulsivity and arousal. When it comes to separation anxiety, many veterinarians think of fluoxetine first. Pachel noted that “fluoxetine is not a bad choice, but it is not always the best choice.” There is an FDA-approved fluoxetine product called Reconcile (PRN Pharmacal), but it can be expensive as a brand name, which should be discussed with the owners. However, Pachel has seen some patients have a better response to the brand name. He recommended starting the brand name for 1 to 3 months if it is in the owner’s budget to see if the drug works before attempting to transition to the generic drug.

Fluoxetine may have a negative impact on appetite, which may be beneficial in cases of food arousal and resource guarding. However, this could also affect the ability of food to help with training. Additional SSRIs include paroxetine, which is less likely to cause anorexia, and sertraline, which tends to have the least number of adverse effects, though may be less successful at treating concurrent conditions with fear and arousal.

The second FDA-approved medication for canine separation anxiety is clomipramine, a TCA that also works well for patients with concurrent impulsivity or anxiety conditions. This medication has more anticholinergic adverse effects and may cause transient sedation.

The final option for maintenance medications is venlafaxine, which is a SNRI. The neurotransmitters most affected by the drug vary by the dosage. At low doses, this drug behaves only as an SSRI. Effects on norepinephrine are not seen until higher doses. Pachel does not recommend this currently as a first-line treatment and noted that there are more adverse effects present during onboarding.

Situational medication options

There are several options for situational medications. However, regardless of which drug is chosen, Pachel recommends administering a trial dose of these medications when the owner is home to monitor for side effects. Then the medication can be trialed in a situation where the patient experiences their fear, anxiety, and/or stress to fine tune dose and frequency. Owners should observe when the medication’s onset of action occurs and how long it appears to help their pet to determine medication frequency.

Medications that may be considered as situational medications include trazodone, clonidine, benzodiazepines, dexmedetomidine oromucosal gel (Sileo; Zoetis), and acepromazine. Although Sileo is an FDA-approved canine product, its use in the treatment of separation anxiety is off-label. There is no short-term, situational medication that is FDA-approved for separation anxiety at this time.

When choosing which medication to prescribe, important considerations include adverse effects, potential for interaction with concurrent medications, and onset of action. For instance, Pachel noted that benzodiazepines have the fastest onset of action and are best for a true panic reaction, but they typically have more side effects, including polyphagia and paradoxical excitation.

Take home points

The combination of behavior modification and pharmaceuticals can greatly improve the quality of life for patients with separation anxiety and their owners. It is important to confirm the diagnosis and learn as much information as possible about the individual patient’s behaviors to select the best medication(s).

Maintenance medications need to be given daily and have a longer onset of action, but they are great for clients with unpredictable, irregular, and potentially chaotic departures or patients who need support for multiple behavioral conditions. Situational medications have a quick onset of duration but short action and are best for short, infrequent, and predictable departures. In some patients, both types of medication are needed.

Ultimately, selecting the best medication for an individual patient requires clear communication with the owner to get a realistic picture of what drug is best and what the client should expect when it comes to treatment.

Kate Boatright, VMD, is a 2013 graduate of the University of Pennsylvania, a practicing veterinarian and freelance speaker and author in western Pennsylvania. She is passionate about mentorship, spectrum of care, and addressing common sources of stress for veterinary teams and recent graduates. Outside of clinical practice, Dr. Boatright is actively involved in organized veterinary medicine.

Reference

Pachel C. Prescribing for separation anxiety: how do you decide? Presented at Fetch dvm360 Conference: Charlotte, NC. March 15, 2025.