URELOG TABLETS (Each film-coated tablet contains (Methyl-2-Oxo Valerate/Calcium-3-Methyl-2-Oxo-Phenylpropionate / Calcium-3-Methyl-2-Oxo-Valerate/ Calcium-DL-2-Hydroxy-4/ L-lysine Acetate/ L-threonine/ L-histine/ L-Tyrosine/ L-tryptophan 101mg/ 86mg/ 68mg/ 67mg/59mg/105mg/53mg/38mg/ 30mg/23mg)

Dosage

Children: Specific paediatric dosing information is not available; refer to a relevant pharmacological reference or clinical guidelines for guidance.

Adults: Specific adult dosing information is not available; refer to a relevant pharmacological reference or clinical guidelines for guidance.

Mechanism of action

While specific mechanisms of action for 3-Methyl-2-oxo are not well established in clinical literature, compounds with similar structures may act as intermediates in metabolic pathways or may exhibit activity through interactions with enzymes or receptors involved in metabolic processes. The precise pathway and effects would depend on the specific context of its use.

Pharmacodynamics

The pharmacodynamics of 3-Methyl-2-oxo are not thoroughly characterized in clinical settings. Generally, compounds of this nature may influence metabolic pathways or cellular functions depending on their interactions with proteins and enzymes in biological systems.

Pharmacokinetics

Information regarding the pharmacokinetics of 3-Methyl-2-oxo is limited. Factors such as absorption, distribution, metabolism, and excretion would be highly dependent on the specific formulation and route of administration, as well as the biological context in which it is used.

Pregnancy

There is insufficient data on the use of 3-methyl-2-oxo in pregnancy. Caution is advised.

Breast-feeding

Data on the excretion of 3-methyl-2-oxo in human milk is not available. Caution is recommended.

Storage

Store in a cool, dry place away from direct light. Keep out of reach of children.

Dosage

Children: Specific dosing guidelines for pediatric populations are not available. Refer to established pediatric dosing references or consult relevant clinical guidelines for similar compounds.

Adults: Specific dosing guidelines for adults are not available. Refer to established protocols or consult relevant clinical guidelines for dosing in similar compounds.

Mechanism of action

The precise mechanism of action of 3-methyl-2-oxophenylpropionate is not well-defined in the literature. However, compounds in this class often interact with various biological pathways, potentially affecting metabolic processes or cellular signaling pathways. Further research is needed to clarify its specific effects at the molecular level.

Pharmacodynamics

Pharmacodynamics data specific to 3-methyl-2-oxophenylpropionate is limited. Generally, similar compounds may demonstrate anti-inflammatory, analgesic, or other pharmacological activities. Mechanisms may include modulation of enzyme activity, receptor interaction, or alteration of signal transduction pathways in cells.

Pharmacokinetics

Information on the pharmacokinetics of 3-methyl-2-oxophenylpropionate, including absorption, distribution, metabolism, and excretion, is not well-documented. Similar compounds typically undergo hepatic metabolism, and their elimination may be influenced by factors such as liver function and other co-administered substances. Detailed pharmacokinetic studies would be necessary to establish a profile for this specific compound.

Pregnancy

There is limited information regarding the safety of 3-methyl-2-oxophenylpropionate during pregnancy. It should be used only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Caution is advised as it is unknown whether 3-methyl-2-oxophenylpropionate is excreted in human breast milk.

Storage

Store in a cool, dry place away from light and moisture.

Dosage

Children: Dosing information for paediatric use of dl2hydroxy4 is not available. Refer to appropriate clinical guidelines or studies for detailed paediatric dosing recommendations.

Adults: Dosing information for dl2hydroxy4 is not available. It is recommended to refer to specific clinical studies or guidelines once they become established.

Mechanism of action

The specific mechanism of action for dl2hydroxy4 is not well-documented in the literature. However, compounds with hydroxyl functionalities typically engage in hydrogen bonding and can influence various biological pathways, potentially affecting enzyme activity or receptor interactions. Further research is needed to elucidate the precise mechanisms at play for this compound.

Pharmacodynamics

Pharmacodynamically, dl2hydroxy4 may influence physiological responses through its interaction with biological molecules. Hydroxy compounds can modulate signaling pathways or alter the pharmacological effects of other drugs. The effects observed will depend on the specific biological context, target systems, and concentrations used.

Pharmacokinetics

The pharmacokinetics of dl2hydroxy4, including absorption, distribution, metabolism, and excretion, have not been extensively studied. Generally, the presence of hydroxyl groups can improve solubility and may influence the compound's bioavailability. Further pharmacokinetic studies are necessary to provide a comprehensive understanding of how this compound behaves in the body.

Pregnancy

Safety during pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether this drug is excreted in human milk. Caution should be exercised when administering to nursing mothers.

Storage

Store at room temperature, away from moisture and light. Keep out of reach of children.

Indications

• Allergic rhinitis
• Urticaria
• Allergic conjunctivitis
• Anaphylactic reactions (as part of combination therapy)

Dosage

Children: Refer to the BNF for Children for appropriate paediatric dosing.

Adults: Refer to established dosing guidelines in relevant professional references.

Mechanism of action

Lhistine acts as a competitive antagonist of the H1 histamine receptor. By binding to these receptors, it prevents histamine from exerting its physiological effects, which include vasodilation, increased vascular permeability, and stimulation of sensory nerves that can lead to symptoms of allergy.

Pharmacodynamics

The pharmacodynamic effects of lhistine include a reduction in the symptoms of allergy through inhibition of histamine-induced responses. It may also exhibit anticholinergic effects, leading to additional drying of secretions and further symptom relief. The onset of action is usually rapid, with peak effects occurring within a few hours of administration.

Pharmacokinetics

Lhistine is absorbed from the gastrointestinal tract and is widely distributed throughout the body. It undergoes hepatic metabolism and is excreted primarily in urine. The half-life of lhistine can vary between individuals, but it generally ranges from several hours to a full day, depending on the formulation and individual patient factors.

Pregnancy

Lhistine has not been well-studied in pregnant populations. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Limited data is available on the excretion of lhistine in human milk. Caution is advised when administering to breastfeeding women.

Storage

Store at room temperature, away from moisture and light. Keep out of reach of children.

Indications

• Herpes simplex virus infections
• Lysine deficiency
• Support in calcium absorption
• Collagen synthesis

Dosage

Children: Refer to the BNF for Children for specific paediatric dosing guidelines.

Adults: Refer to the BNF for specific adult dosing guidelines.

Mechanism of action

Lysine inhibits the replication of herpes simplex virus by altering the amino acid ratio in tissues, particularly decreasing the availability of L-arginine which the virus requires for replication. Additionally, lysine is involved in protein synthesis where it binds with transfer RNA (tRNA) to facilitate the translation process that produces specific proteins.

Pharmacodynamics

Lysine ensures the adequate absorption of calcium, supports collagen formation which is essential for bone, cartilage, and connective tissues, and aids in the production of antibodies, hormones, and enzymes. A deficiency in lysine can lead to various health issues including fatigue, concentration difficulties, irritability, and reproductive problems.

Pharmacokinetics

Lysine is rapidly absorbed from the gastrointestinal tract. It is distributed throughout the body and is primarily excreted via the kidneys. The half-life and detailed metabolic pathways of lysine can vary based on individual physiological conditions and dietary intake.

Adverse effects

• Gastrointestinal disturbances
• Abdominal pain
• Nausea
• Diarrhea

Precautions

• Use with caution in individuals with kidney disease
• Monitor for gastrointestinal effects

Pregnancy

L-lysine is generally considered safe during pregnancy, but clinical advice should be sought.

Breast-feeding

L-lysine is excreted in breast milk, but is typically deemed safe during breastfeeding.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• Tablets
• Capsules
• Powder

Indications

• Protein synthesis support
• Liver health and function
• Digestive health
• Preventing excessive fat accumulation in the liver
• Potential mental health support

Dosage

Children: Refer to BNF for Children for dosing recommendations.

Adults: Refer to BNF for appropriate dosing guidance.

Mechanism of action

L-Threonine acts as a precursor to glycine and serine, facilitating protein synthesis by binding with transfer RNA (tRNA) in the cytoplasm. This binding is essential for the translation process, where specific proteins are synthesized based on the sequence of nucleotides in messenger RNA (mRNA). L-Threonine also functions as a lipotropic agent, preventing excessive fat accumulation in the liver and enhancing nutrient absorption.

Pharmacodynamics

L-Threonine is vital for maintaining protein balance and is necessary for the formation of collagen, elastin, and tooth enamel. It supports liver function and has lipotropic properties when combined with other amino acids, notably aspartic acid and methionine, aiding in the management of fat metabolism. Its role in protein synthesis is continuous, occurring in most cells throughout the body.

Pharmacokinetics

After ingestion, L-Threonine is absorbed in the gastrointestinal tract and utilized in various metabolic pathways, including amino acid biosynthesis and protein synthesis. The amino acid is distributed in the body as it participates in the synthesis of proteins and other biomolecules, with its bioavailability influenced by dietary intake and the presence of other amino acids.

Pregnancy

L-Threonine is generally considered safe during pregnancy, as it is an essential amino acid necessary for normal physiological functions. However, it is advisable to consult a healthcare provider before use.

Breast-feeding

L-Threonine is likely safe during breastfeeding, as it is a naturally occurring amino acid. Nevertheless, mothers should seek guidance from healthcare professionals regarding its use.

Storage

Store in a cool, dry place away from light. Keep out of reach of children.

Indications

• Insomnia
• Anxiety
• Depression
• Migraine headaches
• Chronic pain
• Obsessive-compulsive disorder
• Seasonal affective disorder
• Nutritional supplementation in infant formulas

Dosage

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

During the catabolism of tryptophan, several important side reactions occur, starting with the action of an iron porphyrin oxygenase that opens the indole ring. Kynurenine, a key intermediate, can be converted into kynurenic acid, which exhibits antiexcitotoxic and anticonvulsant properties. Furthermore, tryptophan is involved in producing nicotinic acid, contributing to NAD+ and NADP+ synthesis, and influencing serotonin turnover, which affects thyroid-stimulating hormone and prolactin release.

Pharmacodynamics

Tryptophan is crucial for synthesizing proteins, enzymes, and neurotransmitters, particularly serotonin and melatonin. It can act as a natural relaxant, alleviating insomnia, reducing anxiety and depression, and potentially alleviating migraine headaches. Additionally, it may help in chronic pain management, decrease impulsivity, and treat obsessive-compulsive disorders. Deficiencies in tryptophan can lead to adverse cardiovascular effects, including coronary artery spasms.

Pharmacokinetics

L-Tryptophan is absorbed in the gastrointestinal tract, with its bioavailability influenced by factors such as dietary composition and the presence of competing amino acids. It is metabolized primarily in the liver, with metabolites entering various metabolic pathways, including kynurenine and serotonin synthesis. The pharmacokinetics of tryptophan are affected by transport mechanisms across cell membranes, particularly within the context of tRNA charging and metabolic pathways related to amino acid catabolism.

Adverse effects

• Nausea
• Dizziness
• Drowsiness
• Dry mouth
• Abdominal pain
• Diarrhea

Precautions

• Use with caution in patients with a history of liver disease
• May interact with other medications that affect serotonin levels

Pregnancy

Safety during pregnancy has not been established; use only if clearly needed.

Breast-feeding

It is unknown if tryptophan is excreted in human milk; caution is advised.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• Capsules
• Tablets
• Powder for oral solution

Indications

• Depression
• Stress reduction
• Cognitive enhancement
• Chronic fatigue
• Narcolepsy

Dosage

Children: Refer to the BNF for Children for recommended dosages in paediatric patients.

Adults: Refer to the BNF for specific dosing information, as it varies based on condition and formulation.

Mechanism of action

Tyrosine is produced in cells by hydroxylating phenylalanine. Its antidepressant activity is attributed to its role as a precursor in the synthesis of norepinephrine and dopamine. Elevated levels of these neurotransmitters are believed to contribute to its antidepressant effects.

Pharmacodynamics

L-Tyrosine is critical for synthesizing neurotransmitters, proteins, and enzymes. It can elevate mood, improve cognitive functions, and reduce stress. Its involvement in thyroid hormone production links it to metabolic processes, while deficiencies can manifest in various physiological symptoms, including low blood pressure and body temperature.

Pharmacokinetics

L-Tyrosine is readily absorbed from the gastrointestinal tract. Its metabolism involves conversion to catecholamines via the enzyme tyrosine hydroxylase. It is distributed throughout the body and utilized in protein synthesis as well as neurotransmitter production. The half-life and specific elimination pathways are not well-defined in the provided data.

Adverse effects

• Gastrointestinal disturbances
• Nausea
• Headaches
• Fatigue
• Heartburn

Precautions

• Caution in patients with hyperthyroidism
• Use with caution in patients taking medications for depression

Pregnancy

Limited information is available regarding the safety of L-tyrosine during pregnancy. It is advisable to consult a healthcare professional before use.

Breast-feeding

Limited information is available regarding the safety of L-tyrosine during breastfeeding. Consultation with a healthcare professional is recommended.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Indications

• Metabolic disorders
• Amino acid metabolism disorders
• Potential use in enhancing physical performance

Dosage

Children: Paediatric dosing should be approached with caution and determined based on clinical condition, age, and weight. Refer to specific guidelines for paediatric dosing.

Adults: Dosage should be determined based on individual clinical conditions and should refer to specific guidelines or consult a healthcare professional.

Mechanism of action

Methyl 2-oxo acts as a substrate in metabolic pathways, facilitating the conversion of amino acids into energy. It is involved in the transamination process, where it accepts amino groups, thus playing a role in nitrogen metabolism. It may also act as a precursor in the synthesis of other important biomolecules.

Pharmacodynamics

Methyl 2-oxo influences metabolic pathways by participating in the Krebs cycle and amino acid catabolism, contributing to energy production. It may have effects on muscle metabolism and could enhance physical performance by increasing the availability of energy substrates during exercise.

Pharmacokinetics

The pharmacokinetics of methyl 2-oxo involve absorption through the gastrointestinal tract, followed by hepatic metabolism. The compound is likely to be distributed throughout the body tissues and excreted primarily through the urine after undergoing various metabolic transformations. The half-life and specific metabolic pathways may vary based on individual physiological factors.

Pregnancy

Methyl2oxo should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Consult a healthcare provider for specific guidance.

Breast-feeding

It is not known if methyl2oxo is excreted in human milk. Caution should be exercised when administering to nursing mothers.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Mechanism of action

Proteins of the herpes simplex virus are rich in L-arginine, and tissue culture studies indicate an enhancing effect on viral replication when the amino acid ratio of L-arginine to lysine is high in the tissue culture media. When the ratio of L-lysine to L-arginine is high, viral replication and the cytopathogenicity of herpes simplex virus have been found to be inhibited. L-lysine may facilitate the absorption of calcium from the small intestine. Amino acids are selected for protein synthesis by binding with transfer RNA (tRNA) in the cell cytoplasm. The information on the amino acid sequence of each individual protein is contained in the sequence of nucleotides in the messenger RNA (mRNA) molecules, which are synthesized in the nucleus from regions of DNA by the process of transcription. The mRNA molecules then interact with various tRNA molecules attached to specific amino acids in the cytoplasm to synthesize the specific protein by linking together individual amino acids; this process, known as translation, is regulated by amino acids (e.g., leucine), and hormones. Which specific proteins are expressed in any particular cell and the relative rates at which the different cellular proteins are synthesized, are determined by the relative abundances of the different mRNAs and the availability of specific tRNA-amino acid combinations, and hence by the rate of transcription and the stability of the messages. From a nutritional and metabolic point of view, it is important to recognize that protein synthesis is a continuing process that takes place in most cells of the body. In a steady state, when neither net growth nor protein loss is occurring, protein synthesis is balanced by an equal amount of protein degradation. The major consequence of inadequate protein intakes, or diets low or lacking in specific indispensable amino acids relative to other amino acids (often termed limiting amino acids), is a shift in this balance so that rates of synthesis of some body proteins decrease while protein degradation continues, thus providing an endogenous source of those amino acids most in need. /Amino acids/ The mechanism of intracellular protein degradation, by which protein is hydrolyzed to free amino acids, is more complex and is not as well characterized at the mechanistic level as that of synthesis. A wide variety of different enzymes that are capable of splitting peptide bonds are present in cells. However, the bulk of cellular proteolysis seems to be shared between two multienzyme systems: the lysosomal and proteasomal systems. The lysosome is a membrane-enclosed vesicle inside the cell that contains a variety of proteolytic enzymes and operates mostly at acid pH. Volumes of the cytoplasm are engulfed (autophagy) and are then subjected to the action of the protease enzymes at high concentration. This system is thought to be relatively unselective in most cases, although it can also degrade specific intracellular proteins. The system is highly regulated by hormones such as insulin and glucocorticoids, and by amino acids. The second system is the ATP-dependent ubiquitin-proteasome system, which is present in the cytoplasm. The first step is to join molecules of ubiquitin, a basic 76-amino acid peptide, to lysine residues in the target protein. Several enzymes are involved in this process, which selectively targets proteins for degradation by a second component, the proteasome. /Amino acids/

Pharmacodynamics

Insures the adequate absorption of calcium; helps form collagen ( which makes up bone cartilage & connective tissues); aids in the production of antibodies, hormones & enzymes. Recent studies have shown that Lysine may be effective against herpes by improving the balance of nutrients that reduce viral growth. A deficiency may result in tiredness, inability to concentrate, irritability, bloodshot eyes, retarded growth, hair loss, anemia & reproductive problems.

Mechanism of action

L-Threonine is a precursor to the amino acids glycine and serine. It acts as a lipotropic in controlling fat build-up in the liver. May help combat mental illness and may be very useful in indigestion and intestinal malfunctions. Also, threonine prevents excessive liver fat. Nutrients are more readily absorbed when threonine is present. Amino acids are selected for protein synthesis by binding with transfer RNA (tRNA) in the cell cytoplasm. The information on the amino acid sequence of each individual protein is contained in the sequence of nucleotides in the messenger RNA (mRNA) molecules, which are synthesized in the nucleus from regions of DNA by the process of transcription. The mRNA molecules then interact with various tRNA molecules attached to specific amino acids in the cytoplasm to synthesize the specific protein by linking together individual amino acids; this process, known as translation, is regulated by amino acids (e.g., leucine), and hormones. Which specific proteins are expressed in any particular cell and the relative rates at which the different cellular proteins are synthesized, are determined by the relative abundances of the different mRNAs and the availability of specific tRNA-amino acid combinations, and hence by the rate of transcription and the stability of the messages. From a nutritional and metabolic point of view, it is important to recognize that protein synthesis is a continuing process that takes place in most cells of the body. In a steady state, when neither net growth nor protein loss is occurring, protein synthesis is balanced by an equal amount of protein degradation. The major consequence of inadequate protein intakes, or diets low or lacking in specific indispensable amino acids relative to other amino acids (often termed limiting amino acids), is a shift in this balance so that rates of synthesis of some body proteins decrease while protein degradation continues, thus providing an endogenous source of those amino acids most in need. /Protein synthesis/ The mechanism of intracellular protein degradation, by which protein is hydrolyzed to free amino acids, is more complex and is not as well characterized at the mechanistic level as that of synthesis. A wide variety of different enzymes that are capable of splitting peptide bonds are present in cells. However, the bulk of cellular proteolysis seems to be shared between two multienzyme systems: the lysosomal and proteasomal systems. The lysosome is a membrane-enclosed vesicle inside the cell that contains a variety of proteolytic enzymes and operates mostly at acid pH. Volumes of the cytoplasm are engulfed (autophagy) and are then subjected to the action of the protease enzymes at high concentration. This system is thought to be relatively unselective in most cases, although it can also degrade specific intracellular proteins. The system is highly regulated by hormones such as insulin and glucocorticoids, and by amino acids. The second system is the ATP-dependent ubiquitin-proteasome system, which is present in the cytoplasm. The first step is to join molecules of ubiquitin, a basic 76-amino acid peptide, to lysine residues in the target protein. Several enzymes are involved in this process, which selectively targets proteins for degradation by a second component, the proteasome. /Protein degradation/

Pharmacodynamics

L-Threonine is an essential amino acid that helps to maintain the proper protein balance in the body. It is important for the formation of collagen, elastin, and tooth enamel, and aids liver and lipotropic function when combined with aspartic acid and methionine.

Mechanism of action

A number of important side reactions occur during the catabolism of tryptophan on the pathway to acetoacetate. The first enzyme of the catabolic pathway is an iron porphyrin oxygenase that opens the indole ring. The latter enzyme is highly inducible, its concentration rising almost 10-fold on a diet high in tryptophan. Kynurenine is the first key branch point intermediate in the pathway. Kynurenine undergoes deamniation in a standard transamination reaction yielding kynurenic acid. Kynurenic acid and metabolites have been shown to act as antiexcitotoxics and anticonvulsives. A second side branch reaction produces anthranilic acid plus alanine. Another equivalent of alanine is produced further along the main catabolic pathway, and it is the production of these alanine residues that allows tryptophan to be classified among the glucogenic and ketogenic amino acids. The second important branch point converts kynurenine into 2-amino-3-carboxymuconic semialdehyde, which has two fates. The main flow of carbon elements from this intermediate is to glutarate. An important side reaction in liver is a transamination and several rearrangements to produce limited amounts of nicotinic acid, which leads to production of a small amount of NAD⁺ and NADP⁺. Findings indicate that enhanced rates of serotonin turnover produced by (L)-tryptophan and physical restraint are associated with inhibition of thyroid-stimulating hormone (TSH) and stimulation of prolactin release from anterior pituitary in rats. L-Tryptophan, an indispensable amino acid, serves as a precursor for several small molecules of functional significance including the vitamin niacin, the neurotransmitter serotonin, the metabolite tryptamine, and the pineal hormone melatonin. Increases in tryptophan have been shown to increase synthesis of the neurotransmitters in brain, blood, and other body organs. Amino acids are selected for protein synthesis by binding with transfer RNA (tRNA) in the cell cytoplasm. The information on the amino acid sequence of each individual protein is contained in the sequence of nucleotides in the messenger RNA (mRNA) molecules, which are synthesized in the nucleus from regions of DNA by the process of transcription. The mRNA molecules then interact with various tRNA molecules attached to specific amino acids in the cytoplasm to synthesize the specific protein by linking together individual amino acids; this process, known as translation, is regulated by amino acids (e.g., leucine), and hormones. Which specific proteins are expressed in any particular cell and the relative rates at which the different cellular proteins are synthesized, are determined by the relative abundances of the different mRNAs and the availability of specific tRNA-amino acid combinations, and hence by the rate of transcription and the stability of the messages. From a nutritional and metabolic point of view, it is important to recognize that protein synthesis is a continuing process that takes place in most cells of the body. In a steady state, when neither net growth nor protein loss is occurring, protein synthesis is balanced by an equal amount of protein degradation. The major consequence of inadequate protein intakes, or diets low or lacking in specific indispensable amino acids relative to other amino acids (often termed limiting amino acids), is a shift in this balance so that rates of synthesis of some body proteins decrease while protein degradation continues, thus providing an endogenous source of those amino acids most in need. /Amino acids/ The mechanism of intracellular protein degradation, by which protein is hydrolyzed to free amino acids, is more complex and is not as well characterized at the mechanistic level as that of synthesis. A wide variety of different enzymes that are capable of splitting peptide bonds are present in cells. However, the bulk of cellular proteolysis seems to be shared between two multienzyme systems: the lysosomal and prote

Pharmacodynamics

Tryptophan is critical for the production of the body's proteins, enzymes and muscle tissue. It is also essential for the production of niacin, the synthesis of the neurotransmitter serotonin and melatonin. Tryptophan supplements can be used as natural relaxants to help relieve insomnia. Tryptophan can also reduce anxiety and depression and has been shown to reduce the intensity of migraine headaches. Other promising indications include the relief of chronic pain, reduction of impulsivity or mania and the treatment of obsessive or compulsive disorders. Tryptophan also appears to help the immune system and can reduce the risk of cardiac spasms. Tryptophan deficiencies may lead to coronary artery spasms. Tryptophan is used as an essential nutrient in infant formulas and intravenous feeding. Tryptophan is marketed as a prescription drug (Tryptan) for those who do not seem to respond well to conventional antidepressants. It may also be used to treat those afflicted with seasonal affective disorder (a winter-onset depression). Tryptopan serves as the precursor for the synthesis of serotonin (5-hydroxytryptamine, 5-HT) and melatonin (N-acetyl-5-methoxytryptamine).

Mechanism of action

Tyrosine is produced in cells by hydroxylating the essential amino acid phenylalanine. This relationship is much like that between cysteine and methionine. Half of the phenylalanine required goes into the production of tyrosine; if the diet is rich in tyrosine itself, the requirements for phenylalanine are reduced by about 50%. The mechanism of L-tyrosine's antidepressant activity can be accounted for by the precursor role of L-tyrosine in the synthesis of the neurotransmitters norepinephrine and dopamine. Elevated brain norepinephrine and dopamine levels are thought to be associated with antidepressant effects.

Pharmacodynamics

Tyrosine is a nonessential amino acid synthesized in the body from phenylalanine. Tyrosine is critical for the production of the body's proteins, enzymes and muscle tissue. Tyrosine is a precursor to the neurotransmitters norepinephrine and dopamine. It can act as a mood elevator and an anti-depressant. It may improve memory and increase mental alertness. Tyrosine aids in the production of melanin and plays a critical role in the production of thyroxin (thyroid hormones). Tyrosine deficiencies are manifested by hypothyroidism, low blood pressure and low body temperature. Supplemental tyrosine has been used to reduce stress and combat narcolepsy and chronic fatigue.