In the treatment of depression, one of the most common mental disorders, a large number of therapeutic methods and alternatives have emerged created in order to reduce and eliminate the symptoms.
From pharmacology, attempts have been made to synthesize different types of substances for this purpose. And among the most novel and promising we can find a group that specifically affects different neurotransmitters that are linked to the typical processes of subjects with depression. We are talking about Specific Serotonin and Norepinephrine Reuptake Inhibitors, or SNRIs
Specific serotonin and norepinephrine reuptake inhibitors or SNRIs are a type of antidepressants which are characterized by, as their name suggests, inhibiting or blocking the reuptake of the neurotransmitters serotonin and norepinephrine in the brain.
This implies that the presynaptic neurons will not reabsorb the excess of these neurotransmitters not used by the postsynaptic neuron, so that they will remain in the synaptic space and will be available for the postsynaptic neurons to continue acting. In other words, cause more norepinephrine and serotonin in the brain
We are facing a relatively recent group of drugs, which generally cause few secondary symptoms and, together with the SSRIs, are among the most effective and safe that currently exist. It must be taken into account, however, that as with all antidepressants, there is a period of time of several weeks in which there is no noticeable effect since the brain must and will make changes regarding the brain receptors of these hormones.
Its advantages over other antidepressants are that two of the main monoamines associated with depressive symptoms work as well as the anxious one.
These neurotransmitters They are linked to mood, motivation (especially norepinephrine), the ability to concentrate and attention, treating aspects such as anhedonia, apathy, negative mood and different cognitive and emotional aspects. Furthermore, they do not usually generate histaminergic or cholinergic effects, and side effects associated with these hormones are not common.
Top examples of SNRIs
SNRIs are a group of drugs that share a similar mechanism of action, having different substances with different chemical compositions, properties that, although not the same, generate similar changes at the brain level. Some of the main exponents of this group are the following.
1. Venlafaxine
One of the best-known SNRIs venlafaxine is known for its use as a treatment for depression, being one of the most prescribed drugs of this type and the oldest of them.
It has also been used in cases of social phobia and other anxiety disorders, and has been used in post-traumatic stress disorder. In addition to serotonin and norepinephrine, it also may have some effect on dopamine in high doses
Despite being an SNRI, its effect is much greater on serotonin (it is estimated up to five times more), and even at low doses it can only have an effect on this neurotransmitter.
2. Duloxetine
Another of the most famous and used specific serotonin and norepinephrine reuptake inhibitors, duloxetine is a relatively recent SSRI used for the treatment of major depression (being a highly effective drug in the treatment of this type of symptoms) and other psychological and medical conditions. Also Its role in the treatment of urinary incontinence is known
Antidepressant drug known for its role in the treatment of depressive disorders. It is also prescribed to combat the pain of fibromyalgia and other pain disorders.
4. Levomilnacipran
A psychotropic drug approved in 2013, levomilnacipran is an SSRI whose peculiarity is the fact that its action on norepinephrine practically doubles that of serotonin, making this the most noradrenergic SSRN that currently exists. Very useful in relieving motivational symptoms and improve aspects such as concentration and activity.
5. Desvenlafaxine
Derived from venlafaxine, desvenlafaxine is currently a relevant antidepressant not only for its role in the treatment of depression but also for serving as a treatment for menopause and neuropathic pain. However Its only fully approved clinical indication is depression
Uses and applications
Although all SNRIs are used as antidepressants for the treatment of depression, it is not the only use they may have. Many of them are used in the treatment of different anxiety disorders d, sometimes even with greater preference than substances classified as anxiolytics, as occurs in generalized anxiety disorder or phobias (such as social phobia).
Most of these drugs are also used to treat pain-related conditions, such as fibromyalgia, chronic fatigue syndrome and neuropathies
Risks and side effects
Specific serotonin and norepinephrine reuptake inhibitors They are powerful psychotropic drugs Very useful both in the treatment of depression and other disorders and diseases. However, this does not mean that they cannot generate unpleasant and even dangerous side effects.
As a general rule, these types of drugs tends to cause sedation, gastrointestinal disturbances, nausea and vomiting dry mouth, headache and dizziness, hyperhidrosis, alterations in urination or excretion, sleep problems such as insomnia, sexual disorders such as loss of appetite, erectile dysfunction, ejaculatory problems and reaching orgasm.
Likewise, in some more serious cases arrhythmias and blood pressure alterations may occur. It must also be taken into account that they can generate or facilitate suicidal ideation, especially at the beginning of consumption, and in some cases seizures.
The main contraindications, although they depend on the specific drug, are usually pregnant and lactating women, people with heart, liver or kidney problems. In the case of people with diabetes, they should take special caution and consult their doctor due to the risk of hyperglycemia. They should not be used together with IMAOS either due to the risk of serotonin syndrome, and its use with alcohol or other substances and drugs is contraindicated.
Related article: “MAOIs (monoamine oxidase inhibitors): effects and types”
