Tricyclic antidepressants are one of many types of medication indicated for the treatment of depression. As is well known, some of them can cause dependence and lead to addiction. The advantage of tricyclics is that they do not have this characteristic, so their benefits are often enhanced.
However, as with almost any medication, especially antidepressants, they may have certain contraindications that the health professional will assess to understand whether a patient is suitable for this treatment. For the moment, we will explain the advantages of their use and in which situations, given their side effects, they should be avoided.
What are tricyclic antidepressants?
Tricyclic antidepressants, also known as cyclic antidepressants, are one of the first types of antidepressants developed. Their names are due to the number of rings they have in their chemical structure. If we speak of ‘tricyclic’, it means that they have 3 rings respectively.
These antidepressants were among the first drugs designed to treat depression. Like they do not stimulate the central nervous system or block monoamine oxidase, they are also used to treat conditions such as chronic bedwetting.
Although tricyclic antidepressants are effective, they are not often prescribed as a first treatment because they have been replaced by antidepressants that tend to cause fewer side effects. However, they remain a valuable option when other treatments fail to achieve the desired results, especially in cases of resistant depression. At lower doses, tricyclic antidepressants can even help relieve migraines, manage chronic pain and treat panic disorder.
Origin
Tricyclic antidepressants, sometimes referred to as TCAs, were first developed in the 1950s as a result of research that was not originally focused on treating depression.
Their discovery stems from the observation of unexpected side effects in the development of drugs for other diseases. The main focus during the research was on treating allergies. In the 1940s scientists began to investigate the chemical structure of antihistamines and how they could be used for other medical purposes.
In the 1950s, the Swiss company Geigy developed a new drug for schizophrenia. The compound they were working on, known as imipramine, was a derivative of the tricyclic chemical structure. However, in clinical trials, it was not shown to be effective in treating schizophrenia.
However, it was found to have a notable effect in improving the mood of depressed patients. This finding led to a shift in research focus towards its potential as a treatment for depression. In 1957, imipramine became the first tricyclic antidepressant approved for use in clinical practice. Its success in treating depression led to the development of other TCAs with similar chemical structures.
How do they work?
Neurotransmitters are chemicals found in the brain that play a key role in regulating various bodily functions. Ferritin serotonin and noradrenalin, for example, control mood. In people with depression, a decrease in the number of these 2 neurotransmitters is observed.
Both substances are released from nerve cells to regulate mood, but when they are reabsorbed they no longer exert their effect. Tricyclic antidepressants (TCAs) work by blocking the reabsorption of serotonin and noradrenaline, which prolongs their action in the brain and helps to alleviate the symptoms of depression. In short, tricyclic antidepressants increase the availability of serotonin and noradrenaline in the brain, improving mood. However, they may also influence other brain chemicals and cause side effects (discussed below).
Benefits of tricyclic antidepressants
Tricyclic antidepressants (TCAs) offer several benefits, especially in the treatment of depression and other disorders. Although they have largely been replaced by newer antidepressants with fewer side effects, tricyclics are still used in certain situations because of what they can specifically offer:
Efficacy. TCAs have been shown to be very effective in the treatment of depression, especially in severe cases or those able to resist other treatments.
Treatment of comorbid disorders
In addition to depression, TCAs are useful for treating a variety of other disorders, such as obsessive-compulsive disorder (OCD), anxiety disorders, panic disorder or chronic pain disorders, including migraines and neuropathies.
Best option for some patients
For people who have not responded well to other antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants may be an effective alternative.
Relief of somatic symptoms
TCAs may be beneficial in patients with physical symptoms associated with depression, such as headaches, digestive problems and muscle pain (due to their analgesic properties).
Durability of effect
Compared to other antidepressants, their effects may last longer, which may be useful in the long-term management of depressive symptoms.
Versatility in treatment
TCAs are also used at lower doses for the treatment of conditions such as insomnia, due to their sedative effects.
Although tricyclic antidepressants have several benefits, it is important to keep in mind also their potential side effects, significant in some patients. Therefore, their use is more limited to specific cases, where other options have not been effective.
Side effects of tricyclic antidepressants
Tricyclic antidepressants interfere with various neurotransmitter and receptor systems in the brain, disrupting normal communication between nerve cells. This interference can significantly increase the likelihood of side effects.
When starting treatment with a tricyclic antidepressant, it is common to experience mild symptoms that usually disappear after a few weeks. If these persist, the patient should consult his or her physician to consider alternative options, such as adjusting the dose or switching to another antidepressant. Therefore, it is crucial to weigh the benefits of treatment for depression against possible side effects. The most common include:
Dry mouth.
Es uno de los efectos secundarios más frecuentes y puede ser incómodo, generando problemas como caries o infecciones bucales.
This is one of the most common side effects and can be uncomfortable, leading to problems such as tooth decay or mouth infections.
Drowsiness
Tricyclic antidepressants have a sedative effect, which can cause drowsiness during the day, especially at the beginning of treatment.
Blurred vision
They can affect the ability to focus, causing blurred vision, which usually improves as the body adapts to the medication.
Constipation
The effect of TCAs on the digestive system may slow intestinal transit, leading to constipation.
Urinary retention
Some people may have difficulty urinating due to bladder muscle relaxation.
Weight gain
Prolonged use may be associated with weight gain due to changes in appetite and metabolism.
Dizziness and low blood pressure (orthostatic hypotension).
When standing up quickly, people may experience dizziness or a feeling of faintness due to a drop in blood pressure.
Tachycardia
TCAs can cause an increase in heart rate, which can be worrisome for some people, especially those with heart problems.
Confusion and memory problems
Especially in older people, TCAs can affect cognition, causing confusion, memory problems or disorientation.
Sexual problems
Tricyclic antidepressants may reduce sexual desire (libido), cause difficulty achieving an erection in men or problems reaching orgasm in both sexes.
How to choose the right antidepressant
Each case of depression is unique, so the response to antidepressants may vary from person to person. Genetics are believed to play a role in how antidepressants affect each individual. However, in addition to genetic factors, other factors may also influence the response to medication.
Before prescribing an antidepressant, the physicians in charge of the patient perform, with the help of a laboratory, a an analysis to determine which medication is the most appropriate and safe in this particular case. Among these tests, the most common are usually the electrocardiogram (EKG) and routine blood tests.
Factors to consider
When prescribing tricyclic antidepressants specifically, factors such as:
- The patient’s symptoms.
- Medical history, including family history and previous health problems.
- Other medications he/she is currently taking.
If it does not respond well to the initial tricyclic antidepressant it could mean that the dose is insufficient. In that case, the doctor may order additional blood tests to evaluate the drug levels in the bloodstream.
It usually takes weeks or even longer to notice the effects of tricyclic antidepressant treatment, as well as the reduction of its side effects. Therefore, it is important to be patient and follow the specialist’s instructions. These, for their part, must have professional and trustworthy laboratories, capable of offering all kinds of tests and services that facilitate their analysis and subsequent diagnosis. The Ambar Lab team has more than 3,00 laboratory tests, support in the management of your business and the development of new projects. In addition to testing, we join forces with you to develop technologies, analyze drugs and launch new tests to offer the latest innovations in the market. If you want to know more about our services you can contact our team, who will give you answers more focused on your needs.
