Normally acting as chemical messengers between nerve cells and the brain and body, neurotransmitters can regulate neurological activity, mood, and sleep patterns. Some trigger reactions while others inhibit signals; various messengers that move across neuron synapses can regulate other neurotransmitters or produce ones that are needed. A deficiency or excess of any can cause physical and psychological problems. Neurotransmitter testing, often performed using a blood or urine sample, typically determines the levels of chemical messengers, modulating compounds, or precursor substances. It is often performed for people with conditions like insomnia, anxiety, depression, as well as Attention-Deficit Disorder (ADD).
Neurotransmitters, or endogenous chemicals, are usually sent from the brain to the rest of the body through the blood stream. They can therefore be found in a blood test, but are often filtered out by the kidneys, so neurotransmitter testing often detects excesses through a urine sample. Scientists in a laboratory can analyze these samples to find deficiencies or overloads, as well as look for imbalances in nutrients and hormones that sometimes impact production.
There are tests that can look for levels of inhibitory neurotransmitters, which often regulate other chemicals. These typically calm a person and allow him or her to sleep and be less aggressive. Examples include agmatine, which can counteract the influence of glutamate; this is one of the major excitatory compounds in the brain that often controls brain function, learning, and memory. Excesses of glutamate can kill nerve cells, however, and abnormal levels are often seen in various neurological diseases. Neurotransmitter testing for excitatory chemicals is typically important when someone experiences brain trauma, hypoglycemia, or the symptoms of diseases like Parkinson’s or Alzheimer’s.
Dopamine is a chemical that typically controls the central nervous system as well as cardiovascular and kidney function. It usually helps regulate other hormones too. Neurotransmitter testing is often important for detecting the levels of this chemical, but also for epinephrine, or adrenaline, which it can be converted into. Dopamine is also formed out of tyrosine, an amino acid, so low levels of the neurotransmitter are sometimes traced to a deficiency in the protein.
Neutrotransmitter testing is also performed for chemicals such as Gamma-Amino Butyric Acid (GABA), one of the most prevalent inhibitory chemicals in the brain. Glutamate and its preliminary form glutamine are often tested for as well. Issues with sleep and inflammation often warrant tests for histamine, while compulsion, anxiety, and depression are often treated following neurotransmitter testing of serotonin levels.