A troubling snapshot
The World Health Organization stated that in 2020 depression was the most prevalent mental disease in the world and the second most prevalent disease in general after cardiovascular pathologies. The number of cases, especially during the pandemic and post-pandemic period saw a remarkable increase in the number of mental disorders diagnosed.
WHO estimates that today there are about one billion people suffering from a mental disorder. In fact, depression affects about one in 15 adults (6.7 percent) each year. It is also estimated that one in six people (16.6%) will experience depression at some point in their lives.
The development of increasingly effective drugs to treat depression can help save the lives of thousands of people around the world. How? To understand this, we must first start with the definition of depression, what it is, what causes it, and some of the symptoms.
What is depression?
The term depression is used broadly to describe any depressive condition. However, depressive disorders are different and can be divided on the basis of symptoms or causes.
If we classify disorders according to symptoms:
- major depressive disorder;
- persistent depressive disorder;
- other depressive disorder.
According to causes:
- premenstrual dysphoric disorder;
- depressive disorder associated with or due to another physical condition;
- iatrogenic depressive disorder, that is, induced by substances and/or drugs.
Depression, in general, can cause sadness feelings and loss of interest in daily activities and in addition, can lead to a variety of emotional and physical problems resulting in reduced work and social skills.
Symptoms of depression can range from mild to severe and may include:
- perpetual feeling of a mood of sadness;
- loss of interest or pleasure in everyday activities;
- changes in appetite and sudden weight loss or gain;
- excess or lack of sleep;
- loss of energy or increased fatigue;
- physical restlessness and in movements without a purpose or, conversely, slowing of movements or speech;
- feeling of worthlessness and guilt;
- difficulty in thinking, concentrating or making decisions;
- thoughts of death or suicide.
To be considered as such, symptoms related to a depressive phenomenon must last at least two weeks and represent a change in mood and behavior from the period before the diagnosis.
The right drugs and how they work
Drug treatment depression works by increasing the activity of certain chemicals produced by our brain called neurotransmitters, such as serotonin, norepinephrine, and dopamine. By increasing the activity of these transmitters, it is possible to reduce the main depressive symptoms, which take about 3-4 weeks of action for proven effectiveness.
There are several types of drugs to treat depression. The most common belong to two families:
- SSRI – Selective Serotonin Reuptake Inhibitors (paroxetine and sertraline for example) the mechanism of action intervenes at specific neuronal receptors that prevent serotonin reuptake;
- SNRIs – Serotonin and Norepinephrine Reuptake Inhibitors (venlafaxine and duloxetine for example) – capable of blocking the reuptake (reuptake) of the neurotransmitters serotonin and norepinephrine in the brain.
SSRI drugs are generally the first choice in the treatment of anxiety disorders and depression, as they have fewer side effects than other antidepressants that can result in complaints such as nausea, lightheadedness, dizziness, nervousness, anxiety, fatigability, reduced appetite, and increased blood pressure levels.
The latest generation of new drugs to combat depression
Important molecules with different mechanisms of action have been added in recent months, such as, for example, esketamine and brexanolone. These kinds of drugs have completely different mechanisms of action from those described above because they act on different neurotransmitters: hexketamine on glutamate (a natural amino acid constituent of proteins) and brexanolone on GABA (a substance secreted naturally by our cerebral cortex, which can reduce emotional tension and limit increased stress).
Since there is a significant percentage of depressed patients who do not respond properly to current medications (an estimated 30-40% of cases), resistant clinical cases might find benefit from these new types of drugs that can act differently and on different neurotransmitters.
Are antidepressant drugs safe?
With steadily increasing use worldwide, antidepressants are safe drugs, and this is evidenced by a paper published in the journal Jama Psychiatry stating that „There is no reason not to take them when needed.“ Through a clinical study, a group of European, Asian, U.S. and Canadian researchers drew some very clear conclusions about the safety of antidepressants, evaluating possible differences between patients being treated with antidepressants and healthy people. On the basis of what was observed, Marco Solmi, a researcher in the department of neuroscience at the University of Padua and one of the authors of the study, testifies that „we now know that there is no proven contraindication that would discourage the use of antidepressants“ and adds, „We found that all the adverse health outcomes reported in the observational studies were in fact most likely due to the disease for which the antidepressants were prescribed“.