Anthropometric Measurements as Predictors of Low Birth Weight Among Tanzanian Neonates: A Hospital-Based Study
November 7, 2025
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Brand Name :
Demser
Synonyms :
metyrosine
Class :
Tyrosine Hydroxylase Inhibitors
Brand Name :
Demser
Synonyms :
metyrosine
Class :
Tyrosine Hydroxylase Inhibitors
Dosage Forms & StrengthsÂ
CapsuleÂ
250 mgÂ
Starting dose of 250 mg taken orally every six hours and increase by 250 to 500 mg/day, but not exceeding a maximum of 4 g/day
Maintenance dose of usually 2 to 3 g/day, divided into four equal doses every six hours
Dosing Considerations
Not advised in hypertension
Dosage Forms & StrengthsÂ
CapsuleÂ
250 mgÂ
Refer to adult dosingÂ
it increases the toxicity of metoclopramide
metyrosine: they may increase the toxic effect of bromopride
metyrosine: they may decrease the therapeutic effect of iobenguane radiopharmaceutical products
metyrosine: they may decrease the therapeutic effect of iobenguane radiopharmaceutical products
metyrosine: they may decrease the therapeutic effect of iobenguane radiopharmaceutical products
metyrosine: they may decrease the therapeutic effect of iobenguane radiopharmaceutical products
metyrosine: they may decrease the therapeutic effect of iobenguane radiopharmaceutical products
it may enhance the effects when combined with lofexidine by pharmacodynamic synergism
may increase the hypertensive effect of Monoamine Oxidase Inhibitors
metyrosine: they may increase the toxic effect of antipsychotic agents
metyrosine: they may increase the toxic effect of antipsychotic agents
metyrosine: they may increase the toxic effect of antipsychotic agents
metyrosine: they may increase the toxic effect of antipsychotic agents
metyrosine: they may increase the toxic effect of antipsychotic agents
metyrosine: they may increase the sedative effect of CNS Depressants
metyrosine: they may increase the sedative effect of CNS Depressants
metyrosine: they may increase the sedative effect of CNS Depressants
metyrosine: they may increase the sedative effect of CNS Depressants
metyrosine: they may increase the sedative effect of CNS Depressants
metyrosine: they may increase the toxic effect of promethazine
metyrosine: they may increase toxic effect of vesicular monoamine transporter 2 inhibitors
metyrosine: they may increase toxic effect of vesicular monoamine transporter 2 inhibitors
The sedative effect of metyrosine might be intensified by CNS depressants
The sedative effect of metyrosine might be intensified by CNS depressants
The sedative effect of metyrosine might be intensified by CNS depressants
Could potentially amplify the toxicity of antipsychotic agents
Could potentially amplify the toxicity of antipsychotic agents
Could potentially amplify the toxicity of antipsychotic agents
Could potentially amplify the toxicity of antipsychotic agents
Could potentially amplify the toxicity of antipsychotic agents
metyrosine: they may increase the CNS depressant effect of CNS Depressants
metyrosine: they may increase the CNS depressant effect of CNS Depressants
metyrosine: they may increase the CNS depressant effect of CNS Depressants
metyrosine: they may enhance the serum concentration of CYP2D6 Inhibitors
metyrosine: they may enhance the serum concentration of CYP2D6 Inhibitors
metyrosine: they may enhance the serum concentration of CYP2D6 Inhibitors
metyrosine: they may enhance the serum concentration of CYP2D6 Inhibitors
metyrosine: they may enhance the serum concentration of CYP2D6 Inhibitors
metyrosine: they may increase the sedative effect of CNS stimulants
metyrosine: they may increase the sedative effect of CNS stimulants
metyrosine: they may increase the sedative effect of CNS stimulants
metyrosine: they may increase the sedative effect of CNS stimulants
metyrosine: they may increase the sedative effect of CNS stimulants
may increase the CNS depressant effect of CNS Depressants
Actions and SpectrumÂ
metyrosine works by inhibiting the tyrosine hydroxylase enzyme, which is necessary for the synthesis of catecholamines like adrenaline and noradrenaline. metyrosine decreases the production of these hormones by blocking this enzyme, which can help to lessen the signs and symptoms of pheochromocytoma.Â
metyrosine is not a broad-spectrum medicine in terms of its spectrum because it is primarily used to treat pheochromocytoma and is ineffective for treating other illnesses.Â
Frequency not defined Â
FatigueÂ
NauseaÂ
VomitingÂ
Sexual dysfunctionÂ
CrystalluriaÂ
GalactorrheaÂ
XerostomiaÂ
Nasal stuffinessÂ
DysuriaÂ
Psychic DisturbancesÂ
HeadacheÂ
1-10%Â
Extrapyramidal Symptoms (10%)Â
Diarrhea (10%)Â
>10%Â
Sedation (>20%)Â
Black Box WarningÂ
The black box warning indicates that metyrosine, especially in patients with a history of depression or other psychiatric disorder, can cause depression, including suicidal ideation or suicide. Â
The onset or exacerbation of depression, suicidal thoughts or actions, or other odd changes in mood or behaviour, should all be kept an eye on in patients.Â
Contraindication/Caution:Â
Contraindication:Â
Caution:Â Â
Pregnancy warnings:    Â
Pregnancy category: CÂ
Lactation: Excretion into human milk is unknown Â
Pregnancy Categories:        Â
Category A: Studies that were well-controlled and met expectations revealed no risk to the fetus in either the first or second trimester.Â
Category B: There were lack of studies on pregnant women and no evidence of risk to the foetus in animal experiments.  Â
Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.   Â
Category D: adequate data available with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.  Â
Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.   Â
Category N: There is no data available for the drug under this category
PharmacologyÂ
metyrosine’s pharmacology includes its effects on catecholamine synthesis and release, which are hormones made by the adrenal gland.Â
Tyrosine hydroxylase, an enzyme needed to produce catecholamines like adrenaline and noradrenaline, is inhibited by tyrosine, which is how tyrosine functions. metyrosine works by blocking this enzyme to decrease the production of these hormones, so easing the symptoms of pheochromocytoma and other disorders caused by excess catecholamines.Â
PharmacodynamicsÂ
Tyrosine hydroxylase is responsible for converting the amino acid tyrosine into L-DOPA, which serves as a building block for the creation of catecholamines. Tyrosine hydroxylase is inhibited by metyrosine, which lowers the quantity of L-DOPA that may be used to synthesize catecholamines. This ultimately results in a reduction in catecholamine production and release, which helps to lessen the symptoms of illnesses like pheochromocytoma and several uncommon disorders of excess catecholamine.Â
PharmacokineticsÂ
Absorption  Â
Following oral administration, methylosine is effectively absorbed from the digestive tract. After oral dosing, peak plasma concentrations are attained in 1 to 2 hours. metyrosine can be taken with or without food, but to maintain therapeutic levels, it needs to be taken consistently throughout the day.Â
DistributionÂ
The body produces a lot of methyl tyrosine, and it has been shown to pass the blood-brain barrier. Since only about 30% of metyrosine is bound to proteins, most of it is found in the bloodstream in its free form.Â
MetabolismÂ
The liver is where metyrosine is largely metabolized by the enzymes monoamine oxidase (MAO) and aromatic amino acid decarboxylase (AADC). The 3,4-dihydroxyphenylalanine (DOPA) and 3,4-dihydroxyphenylacetic acid (DOPAC), which are further metabolized and eliminated in the urine, are the primary metabolites of metyrosine.Â
Elimination and excretionÂ
metyrosine is predominantly eliminated in the urine, while minute amounts are also passed in the feces. metyrosine’s elimination half-life is only about 1 to 2 hours, which means numerous daily doses are required to keep therapeutic levels constant.Â
Administration: Â
Oral capsules with metyrosine are available for consumption. To maintain therapeutic levels, the capsules should be taken on an empty stomach or with food at regular intervals.Â
Patient information leafletÂ
Generic Name: metyrosineÂ
Why do we use metyrosine?Â
Pheochromocytoma is a rare tumour that is treated with metyrosine, a drug. Â
Tyrosine hydroxylase, an enzyme involved in the generation of catecholamines, is inhibited by metyrosine in order to function. Â
It can also assist to reduce the levels of catecholamines in the body and relieve the signs and symptoms of pheochromocytoma by blocking this enzyme.Â
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