Amino Acid Therapy

Amino acid therapy may be used to treat a variety of conditions, including Parkinson’s disease, restless leg syndrome, anxiety, depression, attention deficit disorder, addictions, migraines, fibromyalgia, chronic fatigue, and more.

Amino acids are basic building blocks used in the body to build proteins, such as muscle and other tissue, and they also serve as precursors to neurotransmitters.  Humans utilize 20 amino acids and 9 of those are called “essential” because we can’t synthesize them and they must be obtained from our diet.


Neurotransmitters (NTs) are the chemicals in the brain that control our thoughts, emotions, memory, energy, movement, sensation and more.  Some NTs are excitatory and some are inhibitory and the balance of the two is important for optimal brain and body function.

Some amino acids act directly as NTs.  Glutamate and aspartate are excitatory, while glycine and GABA are inhibitory.  The glutamate-GABA system is the main area of clinical significance.

The main neurotransmitters in the brain are serotonin and the catecholamines including dopamine and norepinephrine.  The amino acid precursors and NT function are:

  • Tryptophan -> 5HTP -> Serotonin (mood, appetite, memory)
  • L-Tyrosine -> L-Dopa -> Dopamine (pleasure, reward, motivation) -> Norepinephrine (alertness, concentration, energy)

Amino Acid Therapy

Normally we get all the amino acids we need from our diet.  But with many conditions our diet is not sufficient in providing the large amount of amino acids necessary for full and balanced NT production.  This is when supplementing with specific amino acid blends becomes a valuable treatment.

The main focus with amino acid therapy is on the serotonin-catecholamine system.  When this system is balanced, it seems to control and balance the glutamate-GABA system.

Amino acid therapy is not as simple as giving a standard dosage of amino acids supplements.  The natural production and breakdown of NTs in the body share some of the same enzymes to promote the reactions.  Giving too much of one amino acid can cause a depletion of competing amino acid-NT pathways.

For example, giving only 5HTP will lead to the production of more serotonin, but can deplete the supply of dopamine and norepinephrine.   For this reason it is important to also supply L-Tyrosine.  The key is supplying both in the right amounts.

Testing for Neurotransmitter Balance

Serotonin and dopamine levels throughout the body are primarily controlled by the Organic Cation Transporters Type 2 (OCT-2) which move these NTs and their amino acid precursors in and out of cells, including nerve cells known as neurons.

The only realistic method of predicting NT levels is via urine testing, specifically while saturating the kidney OCT-2 transport systems with amino acids.  A baseline urine sample to assess NT levels is not reliable.  Only once amino acid therapy is established does urinary testing becomes reliable and helpful.

The only lab we know of that can provide this testing is DBS Labs, which analyzes the status of the OCT-2 transporters to guide amino acid therapy.

Many patients do well on the initial amino acid therapy dosages, but if there is not improvement in a week or two then urinary OCT-2 testing is advised.


Protocol 1 (CHK Nutrition)

Neuroreplete 4 caps 2x/day, with breakfast and dinner

Cysreplete 2 caps 3x/day, with lunch, dinner and at bedtime

Protocol 2

L-Tyrosine 500mg 2 caps 2x/day

5HTP 50mg 2 caps 2x/day


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