Carbidopa

Synonyms :
(-)-L-alpha-Hydrazino-3,4-dihydroxy-alpha-methylhydrocinnamic acid monohydrate, (2S)-3-(3,4-Dihydroxyphenyl)-2-hydrazinyl-2-methylpropanoic acid hydrate, (2S)-3-(3,4-Dihydroxyphenyl)-2-hydrazinyl-2-methylpropanoic acid monohydrate, (AlphaS)-alpha-hydrazino-3,4-dihydroxy-alpha-methylbenzenepropanoic acid monohydrate, (S)-(-)-Carbidopa hydrate, (S)-(−)-carbidopa hydrate, (S)-carbidopa hydrate, carbidopa hydrate, Carbidopa monohydrate, Carbidopum, Carbidopum monohydricum, L-alpha-(3,4-Dihydroxybenzyl)-alpha-hydrazinopropionic acid monohydrate

Status : approved

Category

Enzyme Inhibitors

Description

An inhibitor of DOPA decarboxylase, preventing conversion of levodopa to dopamine. It is used in parkinson disease to reduce peripheral adverse effects of levodopa. It has no antiparkinson actions by itself. [PubChem]

Used

For treatment of the symptoms of idiopathic Parkinson’s disease (paralysis agitans), post-encephalitic parkinsonism

Mechanism Of Action

When mixed with levodopa, carbidopa inhibits the peripheral conversion of levodopa to dopamine and the decarboxylation of oxitriptan to serotonin by aromatic L-amino acid decarboxylase. This results in increased amount of levodopa and oxitriptan available for transport to the CNS. Carbidopa also inhibits the metabolism of levodopa in the GI tract, thus, increasing the bioavailability of levodopa.

Dosage

Form Route Strength
Tablet oral 10 mg
Tablet oral 25 mg
Tablet oral 10 mg
Tablet, extended release oral 25 mg
Tablet, orally disintegrating oral 10; 100 mg/1; mg
Tablet, orally disintegrating oral 25; 100 mg/1; mg
Tablet, orally disintegrating oral 25; 250 mg/1; mg
Tablet, film coated oral 100; 200; 25 mg/1; mg/1; mg
Tablet, film coated oral 12.5; 200; 50 mg/1; mg/1; mg
Tablet, film coated oral 125; 200; 31.25 mg/1; mg/1; mg
Tablet, film coated oral 150; 200; 37.5 mg/1; mg/1; mg
Tablet, film coated oral 18.75; 200; 75 mg/1; mg/1; mg
Tablet, film coated oral 200; 200; 50 mg/1; mg/1; mg
Tablet, film coated oral 25; 200; 100 mg/1; mg/1; mg
Tablet, film coated oral 31.25; 200; 125 mg/1; mg/1; mg
Tablet, film coated oral 37.5; 200; 150 mg/1; mg/1; mg
Tablet, film coated oral 50; 200; 12.5 mg/1; mg/1; mg
Tablet, film coated oral 75; 200; 18.75 mg/1; mg/1; mg
Gel intraintestinal (upper) 5 mg
Suspension enteral 20; 4.63 mg/mL; mg/mL
Tablet oral 25 mg
Capsule oral 145; 36.25 mg/1; mg
Capsule oral 195; 48.75 mg/1; mg
Capsule oral 245; 61.25 mg/1; mg
Capsule, extended release oral 95; 23.75 mg/1; mg
Tablet oral 10; 100 mg/1; mg
Tablet oral 25; 100 mg/1; mg
Tablet oral 25; 250 mg/1; mg
Tablet, extended release oral 25; 100 mg/1; mg
Tablet, extended release oral 50; 200 mg/1; mg
Tablet (extended-release) oral 25 mg
Tablet (extended-release) oral 50 mg
Tablet oral 200 mg
Tablet, film coated oral 12.5; 50; 200 mg/1; mg/1; mg
Tablet, film coated oral 18.75; 75; 200 mg/1; mg/1; mg
Tablet, film coated oral 25; 100; 200 mg/1; mg/1; mg
Tablet, film coated oral 31.25; 125; 200 mg/1; mg/1; mg
Tablet, film coated oral 37.5; 150; 200 mg/1; mg/1; mg
Tablet, film coated oral 50; 200; 200 mg/1; mg/1; mg

Pharmacodynamics

Carbidopa, a noncompetitive decarboxylase inhibitor, is used in combination with levodopa for the treatment of Parkinson’s disease.

Toxic Effect

Symptoms of a carbidopa toxicity include muscle spasms or weakness, spasms of the eyelid, nausea, vomiting, diarrhea, an irregular heartbeat, confusion, agitation, hallucinations, and unconsciousness.

Metabolism

The loss of the hydrazine functional group (probably as molecular nitrogen) represents the major metabolic pathway for carbidopa. There are several metabolites of carbidopa metabolism including 3-(3,4-dihydroxyphenyl)-2-methylpropionic acid, 3-(4-hydroxy-3-methoxyphenyl)-2-methylpropionic acid, 3-(3-hydroxyphenyl)-2-methylpropionic acid, 3-(4-hydroxy-3-methoxyphenyl)-2-methyllactic acid, 3-(3-hydroxyphenyl)-2-methyllactic acid, and 3,4-dihydroxyphenylacetone (1,2). [PMID: 4150141]

Absorption

Rapidly decarboxylated to dopamine in extracerebral tissues so that only a small portion of a given dose is transported unchanged to the central nervous system.

Half Life

1-2 hours

Protein Binding

76%

Elimination Route

In clinical pharmacologic studies, simultaneous administration of separate tablets of carbidopa and levodopa produced greater urinary excretion of levodopa in proportion to the excretion of dopamine when compared to the two drugs administered at separate times.

Chemical Classification

This compound belongs to the class of organic compounds known as catecholamines and derivatives. These are compounds containing 4-(2-Aminoethyl)pyrocatechol [4-(2-aminoethyl)benzene-1,2-diol] or a derivative thereof formed by substitution.

Catecholamines and derivatives

Organic compounds

Benzenoids

Benzene and substituted derivatives

Phenols and derivatives

Chemical Name

(-)-L-alpha-Hydrazino-3,4-dihydroxy-alpha-methylhydrocinnamic acid monohydrate

Brands

name Dosage form Country
Apo-levocarb – Tab 10mg/100mg tablet Canada
Apo-levocarb – Tab 25mg/250mg tablet Canada
Apo-levocarb CR tablet (extended-release) Canada
Apo-levocarb CR tablet (extended-release) Canada
Apo-levocarb-tab 25mg/100mg tablet Canada
Carbidopa tablet US
Carbidopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet, orally disintegrating US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet, extended release US
Carbidopa and Levodopa tablet US
Carbidopa and Levodopa tablet US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa and Entacapone tablet, film coated US
Carbidopa, Levodopa, and Entacapone tablet, film coated US
Carbidopa, Levodopa, and Entacapone tablet, film coated US
Carbidopa, Levodopa, and Entacapone tablet, film coated US
Carbidopa, Levodopa, and Entacapone tablet, film coated US
Carbidopa, Levodopa, and Entacapone tablet, film coated US
Carbidopa, Levodopa, and Entacapone tablet, film coated US
Dom-levo-carbidopa tablet Canada
Duodopa gel Canada
Duopa suspension US
Lodosyn tablet US
Lodosyn tablet US
Nu-levocarb – Tab 10mg/100mg tablet Canada
Nu-levocarb – Tab 25 Mg/100 mg tablet Canada
Nu-levocarb – Tablets 25 Mg/250 mg tablet Canada
Parcopa tablet, orally disintegrating US
Parcopa tablet, orally disintegrating US
Parcopa tablet, orally disintegrating US
PMS-levocarb CR tablet (extended-release) Canada
PMS-levocarb CR tablet (extended-release) Canada
Pro-lecarb-100/10 – Tab tablet Canada
Pro-lecarb-100/25 – Tab tablet Canada
Pro-levocarb – 100/25 tablet Canada
Ratio-levodopa/carbidopa tablet Canada
Ratio-levodopa/carbidopa tablet Canada
Ratio-levodopa/carbidopa tablet Canada
Rytary capsule, extended release US
Rytary capsule US
Rytary capsule US
Rytary capsule US
Sinemet tablet US
Sinemet tablet US
Sinemet tablet US
Sinemet 100/10 tablet Canada
Sinemet 100/25 tablet Canada
Sinemet 250/25 tablet Canada
Sinemet CR tablet, extended release US
Sinemet CR tablet, extended release US
Sinemet CR 100/25 tablet (extended-release) Canada
Sinemet CR 200/50 tablet (extended-release) Canada
Stalevo tablet, film coated US
Stalevo tablet, film coated US
Stalevo tablet, film coated US
Stalevo tablet Canada
Stalevo tablet Canada
Stalevo tablet, film coated US
Stalevo tablet, film coated US
Stalevo tablet, film coated US
Stalevo tablet Canada
Stalevo tablet Canada
Stalevo tablet Canada
Teva-levocarbidopa tablet Canada
Teva-levocarbidopa tablet Canada
Teva-levocarbidopa tablet Canada

Drug Drug Interactions

  •  Droxidopa  : Carbidopa may diminish the therapeutic effect of Droxidopa. Carbidopa may decrease serum concentrations of the active metabolite(s) of Droxidopa. Carbidopa may increase the serum concentration of Droxidopa.

Calculated Property

kind Value Source
logP -1.2 ChemAxon
IUPAC Name (2S)-3-(3,4-dihydroxyphenyl)-2-hydrazinyl-2-methylpropanoic acid hydrate ChemAxon
Traditional IUPAC Name carbidopa hydrate ChemAxon
Molecular Weight 244.2444 ChemAxon
Monoisotopic Weight 244.105921632 ChemAxon
SMILES O.C[C@@](CC1=CC(O)=C(O)C=C1)(NN)C(O)=O ChemAxon
Molecular Formula C10H16N2O5 ChemAxon
InChI InChI=1S/C10H14N2O4.H2O/c1-10(12-11,9(15)16)5-6-2-3-7(13)8(14)4-6;/h2-4,12-14H,5,11H2,1H3,(H,15,16);1H2/t10-;/m0./s1 ChemAxon
InChIKey InChIKey=QTAOMKOIBXZKND-PPHPATTJSA-N ChemAxon
Polar Surface Area (PSA) 115.81 ChemAxon
Refractivity 68.77 ChemAxon
Polarizability 21.81 ChemAxon
Rotatable Bond Count 4 ChemAxon
H Bond Acceptor Count 6 ChemAxon
H Bond Donor Count 5 ChemAxon
pKa (strongest acidic) 3.59 ChemAxon
pKa (strongest basic) 5.65 ChemAxon
Physiological Charge -1 ChemAxon
Number of Rings 1 ChemAxon
Bioavailability 1 ChemAxon
Rule of Five 1 ChemAxon
Ghose Filter 0 ChemAxon
MDDR-Like Rule 0 ChemAxon

Affected organism

Humans and other mammals

Target within organism

  • Aromatic-L-amino-acid decarboxylase : in Human