Tricyclic antidepressants (TCAs) are one of the longest used classes of antidepressants. They are still extensively used nowadays. Prior to the invention of selective serotonin reuptake inhibitors (SSRIs), the standard treatment for depression was to use TCA for depression. Tricyclic antidepressants, however, are associated with more side-effects than SSRI's. As a result, TCAs are used only when SSRIs are either not effective or inappropriate.
How Do Tricyclic Antidepressants Work?
It is believed by scientists that depression is caused by an imbalance in neurotransmitters. These are chemicals produced by nerves to communicate with other nerves. Tricyclic antidepressants boost levels of two chemicals, norepinephrine and serotonin, while blockacetylcholine, another neurotransmitters. It is believed by scientists that restoring the balance of these neurotransmitters in the brain will alleviate depression. Not only do tricyclic antidepressants alleviate depression, they also act as a sedative and can block histamine.
What Are the Types of Tricyclic Antidepressants?
There are multiple types of TCAs, which include lofepramine, trazodone, doxepin, mianserin and imipramine. All of these come under different brand names.
Your doctor will have to make a judgment on which one is best for you as there is no one size fits all. Your doctor will take several factors into consideration like:
- Medical history
- Previously prescribed antidepressants
- Other medications you are taking
- Possible side-effects
If the one your doctor has prescribed is ineffective, it may be necessary to change the dose. If a tricyclic antidepressant does not work for you, then another type might be needed.
How Long Should I Take Tricyclic Antidepressants?
Often, it will take a number of weeks or even months for TCAs to improve your mood. Even when the symptoms of depression are alleviated, you may need to continue to take TCAs for six more months. This is to prevent the return of depression. For those that suffer from recurrent depression, it is usual to use antidepressants for at least two years.
Note: Discontinuation of tricyclic antidepressants abruptly can cause the following unwellness:
- Insomnia, increased dreaming, dizziness, lightheadedness, restlessness, anxiety and agitation
- Loss of appetite, diarrhea, vomiting and nausea
- Muscle aches
- Fever and runny nose
What Are the Side Effects of Tricyclic Antidepressants?
Side effects for most people are either minor or none at all. However, the possible side-effects may occur. There will be a leaflet with your prescription, giving a full list of possible side-effects. You need to read this carefully, as well as speak to your pharmacist in advance. The leaflet will list some of the sideeffects, but it is not possible to list them all on this leaflet. As always, make sure to talk to your doctor if any of the side-effects are persistent or troublesome. Your doctor will takethe best action for you, which meansto switch medication or ask you to stop use antidepressants altogether.
1. Common Side Effects
People take TCAs can usually experience dry mouth, blurred vision, constipation, weight loss or gain, low blood pressure, increased heart rate and hives or rash.
2. Severe Side Effects
TCAs may cause drowsiness in some people. Sedation is likely to be greatest in the first month or if the dose is increased. So be aware when you are driving as it may impair your ability.
There is a small risk of fractures in some people. The reason for this increased risk is unclear.
It is possible that taking tricyclic antidepressants will worsen urinary retention and possibly narrow angle glaucoma.
Taking any antidepressant may create problems with sexual function. This includes decreasing libido, delayed orgasm, erectile dysfunction and impaired ejaculation.Allthese sexual problems have been reported while taking tricyclic antidepressants.
3. Suicide and Tricyclic Antidepressants
Antidepressants increase the risk of suicidal thoughts and behaviors, especially in children and adolescents who are suffering from depression or other psychiatric disorders. When planning to use antidepressants for children or adolescents, you must balance the risk with reward. When a child or adolescent has begun therapy,parents should closely monitor for unusual changes or indications inbehavior or thoughts of suicide.
Are There Any Medicines That Can Interact with Tricyclic Antidepressants?
- Monoamine oxidase, tranylcypromine (Parnate) should not be used in conjunction with tricyclic antidepressants. It has been known to cause high fever, convulsionsand even death when combined to use.
- Epinephrine (Adrenalin, Ana-kit, EpiPen, Marcaine, Primatene) should not be used while taking TCAs. They can cause severe high blood pressure.
- Be careful with alcohol since antidepressants are blocked by consumption of alcohol and together, they will increase the sedative effects.
- Using Tagamet (Cimetidine) can increase blood levels and increase side-effects of TCAs.
- Dangerous elevation of blood pressure may result if tricyclic antidepressants are combined with clonidine (Catapres-TTS, Catapres).
- Any combination of TCAs with drugs that inhibit acetylcholine can stop bowl movements and cause paralytic ileus (paralyzing of the intestine.)