-Description-
L-DOPA (3,4-dihydroxy-L-phenylalanine) is a naturally occurring amino acid found in the human brain and in certain plants (Macuna pruriens aka velvet bean). L-Dopa is produced from the amino acid L-Tyrosine via the enzyme tyrosine 3-monooxygenase (previously called tyrosine hydroxylase). Afterwards L-Dopa is able to cross the blood-brain-barrier and converts into Dopamine by the Vitamin B-6 dependant enzyme aromatic-L-amino-acid decarboxylase. Indirectly by increasing Dopamine L-DOPA causes a significant HGH release and suppresses excessive Prolactin release in healthy adults.
Neurochemical effects:
: Raises levels of dopamine
Supports mental alertness and mood
: Releases human growth hormone (HGH)
Supports physical strength and well being
: Reduces excessive Prolactin levels
-Dose-
250-500 mg daily with juice or water.
-When can I feel it?-
Can be noticed within a few hours to a few days.
-What works best with it?-
EGCG (from Green Tea extract) acts as a natural decarboxylase inhibitor which helps prevent excessive levels of Dopamine from building up in the body rather than the brain.
Quercetin acts as a natural catechol-O-methyl transferase (COMT) inhibitor that helps prevent Dopamine breakdown.
-Notes-
Avoid taking in high doses with other compounds that potently affect Dopamine, such as, other dopamine precursors (L-Tyrosine, D-Phenylalanine, L-Phenylalanine), Dopamine agonists Phenylethylamine, Bromocriptine, or MAO-A or B Inhibitors (Deprenyl). If you have hypotension or any health conditions consult a healthcare professional before using.
Some studies:
L-Dopa: Growth hormone releaser
If L-dopa were useful only as a PD treatment, it would be of little interest to most people. Yet L-dopa has uses beyond PD. It has been known for over 30 years that it is an effective stimulant of human growth hormone (HGH) release. In 1970, Boyd and colleagues found that a 500mg oral dose ?"caused a significant rise in plasma growth hormone in PD patients, initially starting therapy or on chronic L-dopa therapy for as long as 11 months. The rise in plasma growth hormone persisted for 120 minutes after the administration of the drug." (4). Boden and his co-workers gave 500mg of the drug orally to four male and five female volunteers. "HGH levels rose sharply at 45 minutes from the basal value of 0.8mg/ml, to a maximum of 10.0mg/ml at 90 minutes (p<0.001) and declined thereafter. This rise occurred in eight of the nine subjects." (5). Hayek and Crawford reported that six out of seven "constitutionally short children" responded to oral L-dopa (200-500mg), "?with elevations in HGH concentration above 7mg/ml, peak levels occurring between 30 and 120 minutes after drug administration..". (6).
In 1975, Ajlouni and colleagues reported the effects of 500mg of oral L-dopa on eight normal and 8 non-obese insulin-dependent diabetic subjects. The normal subjects increased their plasma HGH from 1.5mg/ml before L-dopa, to an average 21mg/ml at 90 minutes post L-dopa, with all subjects showing at least a 10 mg/ml increase. The diabetics increased from 2.5mg/ml to 20mg/ml from 60-90 minutes post L-dopa. Giving 100 grams (3 _ ounces) of glucose with, or 30 minutes after the drug totally suppressed the expected HGH increase (7).
Obesity has been shown to blunt HGH release after oral L-dopa. Laurian and his co-workers tested 17 obese, non-diabetic and six normal weight volunteers. All 17 obese subjects failed to respond to L-dopa, while the normal weight subjects had HGH increases of 10-11mg/ml at 90 and 120 minutes after the drug was administered. The 17 obese men and women subsequently lost 12-50kg. After weight loss, 8 people secreted HGH in response to L-dopa, but at levels only 50-60% of the normal weight people. 9 formerly obese people still failed to respond to it (8).
Barbarino and colleagues gave 500mg orally to 12 obese people, with no significant HGH increases. When some of the subjects were given 40mg oral Propranolol, two hours before L-dopa, they then showed HGH response, although at only 50-75% of the level shown by 12 normal weight subjects given L-dopa, whose serum HGH levels reached 7 to 32mg/ml 60-120 minutes after L-dopa (9).
Greenspan et al. compared HGH response to L-dopa in 44 young patients (31-44 years of age) and 42 older patients (64-88 years of age). All were considered "healthy participants". Plasma HGH increased by 221% in the young patients and 167% in the older patients. The post L-dopa HGH levels were similar in young and old (4.5 and 4.8mg/ml) (10).
The preceding studies illustrate some of the studies showing that 500mg oral L-dopa is an effective stimulator of HGH release. Whether a person is male or female, young or old, diabetic or not, thin or obese (possibly with Propranolol), a PD patient or not, L-dopa is a natural HGH-releasing agent when taken on an empty stomach. For those who can't afford HGH injections, or just don't like self-injecting,L-dopa may provide a reasonable alternative.
L-DOPA Enhances Memory in Healthy Adults
Ann Neurol. 2005 Jul;58(1):121-30
Dopaminergic influences on formation of a motor memory.
Floel A, Breitenstein C, Hummel F, Celnik P, Gingert C, Sawaki L, Knecht S, Cohen LG. Human Cortical Physiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20817, USA.
The ability of the central nervous system to form motor memories, a process contributing to motor learning and skill acquisition, decreases with age. Dopaminergic activity, one of the mechanisms implicated in memory formation, experiences a similar decline with aging. It is possible that restoring dopaminergic function in elderly adults could lead to improved formation of motor memories with training. We studied the influence of a single oral dose of levodopa (100mg) administered preceding training on the ability to encode an elementary motor memory in the primary motor cortex of elderly and young healthy volunteers in a randomized, double-blind, placebo-controlled design. Attention to the task and motor training kinematics were comparable across age groups and sessions. In young subjects, encoding a motor memory under placebo was more prominent than in older subjects, and the encoding process was accelerated by intake of levodopa. In the elderly group, diminished motor memory encoding under placebo was enhanced by intake of levodopa to levels present in younger subjects. Therefore, upregulation of dopaminergic activity accelerated memory formation in young subjects and restored the ability to form a motor memory in elderly subjects; possible mechanisms underlying the beneficial effects of dopaminergic agents on motor learning in neurorehabilitation.
Ann Neurol. 2004 Jul;56(1):20-6
Levodopa: faster and better word learning in normal humans.
Knecht S, Breitenstein C, Bushuven S, Wailke S, Kamping S, Floel A, Zwitserlood P, Ringelstein EB. Department of Neurology, University of Munster, Albert-Schweitzer-Strasse 33, D-48129 Munster, Germany.
[email protected]
Dopamine is a potent modulator of learning and has been implicated in the encoding of stimulus salience. Repetition, however, as required for the acquisition and reacquisition of sensorimotor or cognitive skills (e.g., in aphasia therapy), decreases salience. We here tested whether increasing brain levels of dopamine during repetitive training improves learning success. Forty healthy humans took 100mg of the dopamine precursor levodopa or placebo daily for 5 days in a randomized double-blind and parallel-group design. Ninety minutes later on each day, subjects were trained on an artificial vocabulary using a high-frequency repetitive approach. Levodopa significantly enhanced the speed, overall success, and long-term retention of novel word learning in a dose-dependent manner. These findings indicate new ways to potentiate learning in a variety of domains if conventional training alone fails.
Please Scroll Down to See Forums Below 
