Tricyclic antidepressants

Amitriptyline

Anxiety, aggression, compulsive disorders

Cheaper than many other drugs, but may be more likely to cause adverse effects

Clomipramine

Anxiety, aggression, compulsive disorders, urine marking

Selective serotonin reuptake inhibitors

Fluoxetine

Anxiety, aggression, compulsive disorders, urine marking

May take 3 to 4 weeks before affecting behavior; liquid form may be easier to give to some cats

Paroxetine

Anxiety, aggression, compulsive disorders, urine marking

Sertraline

Anxiety, aggression, compulsive disorders

Azapirones

Buspirone

Anxiety, urine marking

Benzodiazepines

Alprazolam

Anxiety

Longer acting than other drugs of this class

Clonazepam

Anxiety

Also used to control seizures

Diazepam

Anxiety, urine marking

May cause physical dependence; watch for signs of decreased appetite or depression because this drug has been reported to cause severe liver damage in rare cases

Monoamine oxidase inhibitor

Selegiline

Cognitive dysfunction (senility)

Approved for use in dogs, but also used as an extra-label medication in cats