Amitriptyline is a tricyclic antidepressant (TCA) used to treat depression, anxiety and a number of other conditions, including chronic pain and migraine headaches. This antidepressant acts on several chemicals in the brain to relieve anxiety. Major side effects of amitriptyline include drowsiness and dry mouth. Doctors will not prescribe amitriptyline for anxiety to patients who have medical conditions like heart or liver disease. Veterinarians also prescribe amitriptyline for anxiety in small animals.
Doctors may prescribe amitriptyline for anxiety because it works on several chemicals in the brain to relieve feelings of panic. Amitriptyline increases the levels of neurotransmitters, including serotonin and norepinephrine. Serotonin contributes to positive feelings of well-being, while norepinephrine increases alertness and enhances memory. Norepinephrine also enhances the effect of endorphins, which is another neurotransmitter that contributes to feelings of comfort and happiness.
Drugs developed for humans are often used to treat diseases or disorders in animals. Veterinarians sometimes prescribe amitriptyline for anxiety in pets. This drug may be prescribed to cats who urinate outside the litter box, as well as for cats with urinary tract disease. It is prescribed for separation anxiety and other anxiety disorders in animals like excessive grooming. Much lower doses of this drug are needed in animals than humans, so the drug must be prescribed by a veterinarian to ensure proper dosage.
Drowsiness and dry mouth are two of the major side effects of amitriptyline. The drug’s sedating influence is the result of its effect on serotonin. Other side effects of amitriptyline include nausea, nightmares, blurred vision and constipation. Some of the most serious side effects can be chest pain, rapid heartbeat, and altered blood sugar levels.
Amitriptyline is not recommended for pregnant women or women who are nursing. Doctors might also consider prescribing a different drug for patients with heart conditions or who are diabetic. Amitriptyline is broken down in the liver, so it may not be the drug of choice for patients with impaired liver function. Patients should not take amitriptyline and methimazole together because it can produce low white blood cell counts. Doctors prescribe methimazole when the thyroid produces too many hormones.
Approved for use in the United States in 1961, amitriptyline has a wide number of uses. While it is often prescribed for depression, amitriptyline is also effective in treating anxiety, panic disorder and post-traumatic stress syndrome. Amitriptyline is sometimes prescribed for eating disorders, bipolar disorder and attention deficit hyperactivity disorder. Doctors may also prescribe amitriptyline for pain caused by a variety of conditions such as fibromyalgia, irritable bowel syndrome, migraine headaches and interstitial cystitis. Treatment of pain usually requires lower doses of amitriptyline than for other conditions.