Can GABA be measured?
Neurotransmitters such as gamma-amino-butyric acid ( GABA for short) perform important tasks in the body. A deficiency of the neurotransmitters can have negative consequences, cause health complaints or promote the development of diseases. To prevent this, it can be helpful to measure neurotransmitter levels. In the case of GABA, however, this is not so easy, because the neurotransmitter cannot easily enter the brain from the bloodstream.
Measuring the GABA level
Gamma-amino-butyric acid (GABA) cannot cross the blood-brain barrier, or only to a small extent. Therefore, the level of GABA in the brain cannot be derived from blood plasma. However, since it is precisely this that may be of interest, other approaches are required. One possible method for determining GABA levels in the brain is magnetic resonance imaging (MRI). MRI is an imaging technique that visualizes metabolic processes in the brain.
However, since the procedure is very complex and expensive to perform, it is generally only used in justified individual cases or for research purposes. For example, U.S. scientists were able to show that depressed subjects have significantly lower GABA concentrations in a specific brain area compared to healthy controls  or that the amount of GABA in the brain is related to cognitive performance and specifically to working memory performance .
In most cases, however, such a measurement is too costly. In that case, GABA deficiency can often be detected or inferred from symptoms. Typical complaints include inner restlessness and insomnia, irritability and mood swings, anxiety, cold sweats, muscle aches and headaches, and concentration problems. However, these symptoms are relatively unspecific and can have very different causes. For successful therapy, it is imperative to identify the causes of the symptoms in order to select an appropriate treatment. If they are based on a GABA deficiency, they will improve noticeably by increasing the GABA level. Such relief of symptoms and improvement in well-being often serves as evidence for the diagnosis and appropriate treatment, without actually having to measure GABA with the complex and expensive MRI method.
Conclusion on measuring GABA
If you want to measure GABA to determine your neurotransmitter level in the brain, you have to resort to a relatively complex and expensive procedure: Only with the help of magnetic resonance imaging can GABA be measured here. A simple blood test is not sufficient in this case, because the neurotransmitter cannot cross the blood-brain barrier. This means that the amount of GABA in the blood plasma does not have to correspond to the amount in the brain.