Occasionally a cat develops behavior problems, such as inappropriate litter box use, rough play or difficulty living with other cats. The American Society for the Prevention of Cruelty to Animals notes that medication combined with behavior modification can be an effective way to address cat behavior issues. Amitriptyline is one of the medications the vet may turn to to help with cat behavior problems, however it reacts with a variety of other medication and carries potential side effects, including drowsiness, vomiting and decreased urination.
Amitriptyline: A Tricyclic Antidepressant
Amitriptyline is a tricyclic antidepressant, which increases two of the neurotransmitters responsible for regulating emotional activity. Tricyclic antidepressants have expanded beyond their original use for people as anxiety, anger and compulsive behavior managers, to helping treat compulsive behavior in cats, such as excessive grooming, inappropriate urination and anxiety. Available in tablets or as an injectable, amitriptyline is also available in the branded form known as Elavil.
Side Effects of Amitriptyline
The most common side effect from amitriptyline is drowsiness. A cat taking the drug also may gain weight, become constipated and urinate less frequently. If she licks her lips more than normal, she may be experiencing dry mouth as a side effect of the medication. Dry eyes, vomiting and hyperexcitability are also potential effects of amitriptyline. Mar Vista Animal Medical Center in Los Angeles, California notes that "cardiac rhythm disturbance" is the most potentially dangerous side effect and recommends electrocardiogram screening for a cat before beginning treatment with amitriptyline.
Cautions and Contraindications of Amitriptyline
Tricyclic antidepressants may affect blood sugar levels, so diabetic cats should not take this medicaton. Amitriptyline is removed from the body by the liver, making periodic testing to monitor liver enzyme values necessary. Amitriptyline may react with a variety of medications, including anti-thyroid drugs such as methimazole. Other potential pharmaceutical reactions include central nervous system depressants such as diazepam and monoamine oxidase inhibitors such as deprenyl. Pregnant and lactating cats should avoid using amitriptyline.
Too much amitriptyline can have fatal effects on the heart. A cat who takes too much of the medication should see a veterinarian promptly.