ArticleLast Updated June 20182 min read
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Benzodiazepine Sedative/Tranquilizer (Systemic Drug)

Prescriber Highlights

Used for adjunctive behavioral treatment in dogs and cats, especially for prophylaxis of anxiety triggered by storms, fireworks, and similar events

C-IV controlled substance

Uses, Indications

  • Useful for adjunctive therapy in anxious, aggressive dogs, or animals demonstrating panic reactions

  • Most effective when used before a triggering event

  • May be useful in treating anxiety disorders in cats

  • Unlike oral diazepam, alprazolam has not been implicated in causing liver failure in cats

Contraindications, Precautions, Warnings

  • Contraindications

Some veterinarians believe alprazolam is contraindicated in aggressive patients, as anxiety may restrain animals from aggressive tendencies. This remains controversial. 

  • Precautions

Patients with impaired hepatic or renal function or narrow angle glaucoma; debilitated or geriatric patients 

  • Warnings

May impair working animal performance; has potential for human abuse and drug diversion

Side Effects

  • Sedation, transient ataxia, and increased appetite

  • In cats, irritability, depression, increased affection, and aberrant demeanor are also possible 

  • Rarely, dogs may exhibit a contradictory response (eg, CNS excitement including increased aggression, anxiety, agitation)

Drug Interactions*

  • May increase serum levels of tricyclic antidepressants (eg, amitriptyline, clomipramine) and digoxin

  • Alprazolam metabolism may decrease when used with hepatically metabolized drugs (eg, cimetidine, erythromycin, ketoconazole, itraconazole)

  • Additive effects may occur when used with other CNS depressant agents (eg, barbiturates, narcotics, anesthetics) 

  • Fluoxetine and fluvoxamine may increase serum alprazolam levels

*Not a complete list


  • Clinical efficacy and side effects

  • Consider monitoring hepatic enzymes in cats when used long term

Client Information

  • Administer alprazolam 30 minutes to 1 hour prior to triggering events

  • Most common side effect is drowsiness, but excitement and behavioral changes (eg, increased appetite), although rare, may occur, especially in cats

  • Immediately report yellowing of the gums, skin, or whites of the eyes

Dosage Forms

  • The following are human-labeled products available for veterinary off-label use:

    • Alprazolam oral tablets: 0.25 mg, 0.5 mg, 1 mg, and 2 mg

    • Alprazolam extended-release oral tablets: 0.5 mg, 1 mg, 2 mg, and 3 mg

    • Alprazolam orally disintegrating tablets: 0.25 mg, 0.5 mg, 1 mg, and 2 mg

    • Alprazolam oral solution: 1 mg/mL in 30 mL

Compiled and summarized from Plumb’s® Veterinary Drugs by Shannon Palermo, VMD