Gamma-Aminobutyric Acid (GABA)
(Gamma-aminobutyric acid)

General Info

Active Forms
GABA.

Absorption
Like other amino acids, when GABA is taken orally, it is absorbed from the small intestines.

Dietary Sources
GABA is not found in significant amounts in foods. Almost all the body's source of GABA is synthesized.

Dosage Info

Dosage Range 200mg, 4 times a day up to 10 grams daily. Most Common Dosage 200mg, 4 times a day. Dosage Forms Capsules, tablets, and powder.		Adult RDI None established Adult ODA None established

Overview

GABA is a non-essential amino acid found in high concentrations throughout the central nervous system. Both glutamine and glutamic acid are amino acids that can function as precursors for synthesis of GABA. GABA is also an inhibitory neurotransmitter that functions in the central nervous system by decreasing neuronal activity. It is frequently referred to as the brain's natural calming agent. Benzodiazepines bind to the GABA receptors in the brain, which produces their characteristic antianxiety effects. Other hypotics (ambien/sonata) and several anticonvulsants also enhance GABA function. Benzodiazepines function by stimulating GABA receptors. Some research supports using GABA to facilitate withdrawal from benzodiazepine medications.(1)

Toxicities & Precautions

Like other amino acids, when GABA is taken orally, it is absorbed from the small intestines.

General
There is no known toxicity associated with GABA.

Side Effects
People taking large doses (multiple grams) occasionally report mild nausea, a slight shortness of breath that lasts for a few minutes, and a transient tingling of the skin.(2)

Functions in the Body

Uses

Clinical Applications
	Anxiety
	Body-Building
	Epilepsy

Human Growth Hormone (hGH) Secrection:
GABA reportedly stimulates or enhances the secretion of hGH.(3)

Inhibitory Neurotransmitter:
An abundant inhibitory neurotransmitter in the brain. Significant amounts of GABA produced in glands controlled by the sympathetic nervous system.

Clinical Applications

Anxiety
Drugs such as benzodiazepines and barbiturates provide their antianxiety effects by selectively binding to GABA receptors.(4) Knowledge of GABA's role as a calming neurotransmitter has led people to take GABA to relieve anxiety.(5)

Body-Building
Doses of GABA cause an increase in plasma growth hormone.(6)Studies like this have attracted the attention of body builders who take GABA at bedtime to stimulate muscle growth. GABA is one of the main ingredients in products that are marketed as growth hormone precursors to naturally stimulate the endocrine system to secrete endogenous growth hormone.

Epilepsy
Results from both animal and human studies suggest that GABA plays an important role in the mechanism and treatment of epilepsy.(7) Since discovering that GABA plays a role in controlling seizures, drugs that augment GABA's uptake and enhance its delivery to the brain have been developed. For example, gabapentin enhances the release of GABA in the hippocampus,(8) tiagabine increases GABA levels by inhibiting reuptake,(9) and vigabatrin reduces the catabolism of GABA.(10)

Symptoms & Causes of Deficiency

Reports of GABA deficiency in the scientific literature are uncommon. However, symptoms associated with GABA deficiency include depression,(11) sleep disorders, primarily associated with early morning awakening, constipation and headaches located in the back of the head and neck.(12) A deficiency of vitamin B6 could lead to a GABA deficiency since glutamic acid decarboxylase (GAD), the enzyme that synthesizes GABA, is vitamin B6 dependent.(13)

Footnotes

¹ Braverman ER, et al. The Healing Nutrients Within. New Canaan, CT: Keats Publishing, Inc; 1997:247.
² Braverman ER, et al. The Healing Nutrients Within. New Canaan,CT: Keats Publishing, Inc; 1997:257-58.
³ Mezo I, et al. New Gaba-containing Analogues of Human Growth Hormone-releasing Hormone (1-30)-amide: I. Synthesis and in Vitro Biological Activity. J Endocrinol Invest. Nov1993;16(10):793-98.
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⁴ Enna SJ, et al. Role of Gamma-aminobutyric Acid in Anxiety. Psychopathology. 1984;17(Suppl1):15-24.
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⁵ Goddard AW, Mason GF, Almai A. Reductions in occipital cortex GABA levels in panic disorder detected with 1h-magnetic resonance spectroscopy. Arch Gen Psychiatry. Jun2001;58(6):556-61.
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⁶ Cavagnini F, et al. Effect of Acute and Repeated Administration of Gamma aminobutyric Acid (GABA) on Growth Hormone and Prolactin Secretion in Man. Acta Endocrinol.(Copenh). Feb1980;93(2):149-54.
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⁷ Treiman DM. Gabaergic mechanisms in epilepsy. Epilepsia. 2001;42(Suppl3):8-12.
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⁸ Kelly KM. Gabapentin. Antiepileptic Mechanism of Action. Neuropsychobiology. Oct1998;38(3):139-44.
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⁹ Shinnar S. Tiagabine. Semin Pediatr Neurol. Mar1997;4(1):24-33.
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¹⁰ Shields WD, et al. Vigabatrin. Semin Pediatr Neurol. Mar1997;4(1):43-50.
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¹¹ Sanacora G, Gueorguieva R, Epperson CN, et al. Subtype-specific alterations of gamma-aminobutyric acid and glutamate in patients with major depression. Arch Gen Psychiatry. Jul2004;61(7):705-13.
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¹² Cocchi R. A Syndrome from a Possible GABA Deficiency. Clinical-therapeutic Report on 15 Cases. Acta Psychiatr Belg. Apr1978;78(2):407-24.
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¹³ Gospe SM Jr, et al. Reduced GABA Synthesis in Pyridoxine-dependent Seizures. Lancet. May1994;343(8906):1133-34.
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Gamma-Aminobutyric Acid (GABA)(Gamma-aminobutyric acid)

Gamma-Aminobutyric Acid (GABA)
(Gamma-aminobutyric acid)