How does a serotonin deficiency manifest itself?

When there is a very low concentration of the messenger substance serotonin in the body, physicians speak of a serotonin deficiency. In order to diagnose a serotonin deficiency, the hydroxyindoleacetic acid, which is the main breakdown product of serotonin, is measured first and foremost. A deficiency of serotonin can lead to various complaints.

How does serotonin deficiency manifest itself?

Due to the variety of bodily functions and processes in which serotonin is involved, a serotonin deficiency can also manifest itself in very different ways. Symptoms that can be caused by a deficiency of serotonin include:

• severe fatigue
• listlessness
• concentration problems
• bad mood
• increased irritability
• increased anxiety
• more intense perception of pain

However, a serotonin deficiency can have not only psychological but also physical consequences and manifest itself in physical complaints. Frequently observed symptoms include headaches or muscle pain, high blood pressure or sleep disorders.

In addition, there are some diseases that science assumes are caused by a serotonin deficiency or that are at least related to serotonin. These include, first and foremost, mental illnesses such as depression. A common treatment for depression is the use of so-called serotonin reuptake inhibitors (SSRIs). These agents act as antidepressants by blocking serotonin transporters, thereby increasing the concentration of serotonin in the brain.

But other conditions also appear to be associated with a serotonin deficit. Studies suggest that various ailments can be alleviated by increasing serotonin levels. This is true, for example, for migraine [1], as well as for irritable bowel syndrome [2]. For successful treatment of these diseases, it is therefore of great importance to check whether there is actually a deficiency of serotonin.

How can a serotonin deficiency be detected?

However, the symptoms and complaints caused by a deficiency of serotonin are relatively non-specific and may have other causes. Although successful administration of SSRIs indicates a previous deficiency of serotonin, it is not always useful or necessary to take antidepressants.

Specific tests are needed to be sure that a serotonin deficiency is indeed present. These usually measure hydroxyindoleacetic acid in the urine. Hydroxyindoleacetic acid (5-HIES) is formed when the body breaks down serotonin. This breakdown product is excreted by the kidneys, so the amount of 5-HIES in the urine can be determined. From this, conclusions can be drawn about the approximate serotonin level in the body.

Conclusion on recognizing serotonin deficiency

A serotonin deficiency can manifest itself in relatively unspecific complaints such as fatigue, concentration problems, irritability, anxiety or an increased perception of pain. Diseases such as depression, migraine or irritable bowel syndrome can also be the result of a serotonin deficiency. However, a specific test, which usually measures serotonin degradation products in the urine, is required for a corresponding diagnosis.

Sources

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4117050/
[2] https://pubmed.ncbi.nlm.nih.gov/19361459/