Generic Name:
amantadine hydrochloride

Trade Name:
Symmetrel ® [Endo]

IUPAC Name:
adamantan-1-amine hydrochloride

Dosage Forms/Routes:
Tablet/oral;
Syrup/oral;
Capsule/oral

Major Metabolite:
acetylamantadine

Database Search Links:
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Initial Approval:
11/03/1980

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₀H₁₈ClN

Molecular Mass:
187.709 g/mol

Indications:
Amantadine is indicated in the treatment of parkinsonism and drug-induced extrapyramidal reactions. Amantadine is also indicated for the prophylaxis and treatment of signs and symptoms of infection caused by various strains of influenza A virus.

Possible Mechanisms of Action:
At NMDA receptors, amantadine stabilizes closed channel states by accelerating channel closure; it also inhibits current flow through open NMDA receptor channels to a lesser degree (1). Amantadine's effects on NMDA receptors are greatest in the striatum (2). The drug may also decrease the rate of reactivation and act as a noncompetitive open channel blocker at nicotinic acetylcholine receptors such as those that contain the alpha7 subunit (3). In addition, amantadine is a weak agonist at sigma-1 receptors (4). Amantadine's antiviral utility results from its blockade of the influenza A virus M2 membrane protein (5). M2 proteins form proton-selective ion channels (6).

Chemical Class:
tricyclic amine

PubChem 2D Structure:

Generic Name:
apomorphine hydrochloride

Trade Name:
Apokyn ® [Mylan Bertek]

Common Chemical Name:
6ab-Aporphine-10,11-diol
hydrochloride hemihydrate

Dosage Forms/Routes:
Injectable/subcutaneous

Major Metabolite:
8-oxo-apomorphine-
semiquinone

Database Search Links:
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[Search PubMed for
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[PDSP K_i database]

Initial Approval:
04/20/2004

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₃₄H₃₈Cl₂N₂O₅

Molecular Mass:
625.581 g/mol

Indications:
Apomorphine is indicated for the acute, intermittent treatment of hypomobility, "off" episodes ("end-of-dose wearing off" and unpredictable "on/off" episodes) associated with advanced Parkinson’s disease. Apomorphine has been studied as an adjunct to other medications (see CLINICAL PHARMACOLOGY: Clinical Trials in the prescribing information).

Chemical Class:
aporphine alkaloid of the dibenzoquinoline class

PubChem 2D Structure:

"3D" Structure (Requires Chime):
[Link] 

Generic Name:
benztropine mesylate

Trade Name:
Cogentin ® [Merck]

IUPAC Name:
3-benzhydryloxy-8-methyl-8-
azabicyclo[3.2.1]octane;
methanesulfonic acid

Dosage Forms/Routes:
Tablet/oral;
Injectable/injection

Major Metabolites:
N-desmethylbenztropine;
benztropine N-oxide

Database Search Links:
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[Search PubMed for
Randomized Controlled Trials]
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Initial Approval:
03/05/1954

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₂₂H₂₉NO₄S

Molecular Mass:
403.536 g/mol

Indications:
Benztropine is indicated for use as an adjunct in the therapy of all forms of parkinsonism. The drug is also useful in the control of extrapyramidal disorders (except tardive dyskinesia) due to neuroleptic drugs (e.g., phenothiazines).

Chemical Class:
tropanol derivative

PubChem 2D Structure:

Generic Name:
biperiden hydrochloride

Trade Name:
Akineton ® [Abbott, Par]

IUPAC Name:
1-(5-bicyclo[2.2.1]hept-2-
enyl)-1-phenyl-3-(1-
piperidyl)propan-1-ol
hydrochloride

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
Unknown

Database Search Links:
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Randomized Controlled Trials]
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[PDSP K_i database]

Initial Approval:
09/08/1959

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₂₁H₃₀ClNO

Molecular Mass:
347.922 g/mol

Indications:
Benztropine is indicated for use as an adjunct in the therapy of all forms of parkinsonism (idiopathic, postencephalitic, arteriosclerotic). The drug is also useful in the control of extrapyramidal disorders due to neuroleptic drugs (e.g. phenothiazines).

PubChem 2D Structure:

Generic Name:
bromocriptine mesylate

Trade Name:
Parlodel ® [Novartis]

Common Chemical Name:
ergotaman-3’,6’,18-trione,2-
bromo-12'-hydroxy-2'- (1-
methylethyl)-5'-(2-
methylpropyl)-,(5'a)
monomethanesulfonate (salt)

Dosage Forms/Routes:
Tablet/oral;
Capsule/oral

Major Metabolites:
2-bromolysergic acid;
2-bromoisolysergic acid

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
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[PDSP K_i database]

Initial Approval:
06/28/1978

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₃₃H₄₄BrN₅O₈S

Molecular Mass:
750.701 g/mol

Possible Mechanisms of Action:
Bromocriptine is an agonist at dopamine D2 and D3 receptors (7, 10). Bromocriptine also binds to alpha-1A-adrenoceptors, alpha-1B-a drenoceptors, alpha-1D-adrenoceptors, alpha-2A-adrenoceptors, alpha-2B-adrenoceptors, and alpha-2C-adrenoceptors (10). The drug may also bind to serotonin 5-HT1A (10), 5-HT1D (10), 5-HT2B (10), and 5-HT7 receptors (17). In addition, bromocriptine may accelerate the transport of glutamate mediated by hGluT-1 (29). The drug is also a potent free radical scavenger (30).

Indications:
Bromocriptine mesylate is in the treatment of the signs and symptoms of idiopathic or postencephalitic Parkinson’s disease. As adjunctive treatment to levodopa (alone or with a peripheral decarboxylase inhibitor), bromocriptine mesylate therapy may provide additional therapeutic benefits in those patients who are currently maintained on optimal dosages of levodopa, those who are beginning to deteriorate (develop tolerance) to levodopa therapy, and those who are experiencing “end of dose failure” on levodopa therapy. Bromocriptine mesylate therapy may permit a reduction of the maintenance dose of levodopa and, thus may ameliorate the occurrence and/or severity of adverse reactions associated with long-term levodopa therapy such as abnormal involuntary movements (e.g., dyskinesias) and the marked swings in motor function (“on-off” phenomenon). Continued efficacy of bromocriptine mesylate therapy during treatment of more than 2 years has not been established.

Data are insufficient to evaluate potential benefit from treating newly diagnosed Parkinson’s disease with bromocriptine mesylate. Studies have shown, however, significantly more adverse reactions (notably nausea, hallucinations, confusion and hypotension) in bromocriptine mesylate treated patients than in levodopa/carbidopa treated patients. Patients unresponsive to levodopa are poor candidates for bromocriptine mesylate therapy.

See the prescribing information for information about indications related to hyperprolactinemia-associated dysfunctions and acromegaly.

Chemical Class:
ergot derivative

PubChem 2D Structure:

Generic Name:
carbidopa

Trade Name:
Lodosyn ® [Bristol-Myers Squibb]

IUPAC Name:
3-(3,4-dihydroxyphenyl)-2-
hydrazinyl-2-methyl-propanoic
acid hydrate

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
a-methyl-3-methoxy-4-
hydroxyphenylpropionic acid;
a-methyl-3,4-
dihydroxyphenylpropionic acid

Database Search Links:
[PubMed]
[Search PubMed for
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[PDSP K_i database]

Initial Approval:
04/25/1977

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₀H₁₆N₂O₅

Molecular Mass:
244.245 g/mol

Possible Mechanisms of Action:
Carbidopa is a peripheral aromatic L-amino acid decarboxylase (AADC) inhibitor (18). The drug, which does not cross the blood-brain barrier, is combined with levodopa to prevent its conversion to dopamine in the periphery (18).

Indications:
Lodosyn is indicated for use with Sinemet (carbidopa-levodopa) or with levodopa in the treatment of the symptoms of idiopathic Parkinson's disease (paralysis agitans), postencephalitic parkinsonism, and symptomatic parkinsonism which may follow injury to the nervous system by carbon monoxide intoxication and/or manganese intoxication.

Lodosyn is for use with Sinemet (carbidopa-levodopa) in patients for whom the dosage of SINEMET (carbidopa-levodopa) provides less than adequate daily dosage (usually 70 mg daily) of carbidopa.

Lodosyn is for use with levodopa in the occasional patient whose dosage requirement of carbidopa and levodopa necessitates separate titration of each entity.

Lodosyn is used with Sinemet (carbidopa-levodopa) or with levodopa to permit the administration of lower doses of levodopa with reduced nausea and vomiting, more rapid dosage titration, and with a somewhat smoother response. However, patients with markedly irregular ("on-off") responses to levodopa have not been shown to benefit from the addition of carbidopa.

Since carbidopa prevents the reversal of levodopa effects caused by pyridoxine, supplemental pyridoxine (vitamin B6), can be given to patients when they are receiving carbidopa and levodopa concomitantly or as Sinemet (carbidopa-levodopa).

Although the administration of Lodosyn permits control of parkinsonism and Parkinson's disease with much lower doses of levodopa, there is no conclusive evidence at present that this is beneficial other than in reducing nausea and vomiting, permitting more rapid titration, and providing a somewhat smoother response to levodopa.

Certain patients who responded poorly to levodopa alone have improved when carbidopa and levodopa were given concurrently. This was most likely due to decreased peripheral decarboxylation of levodopa rather than to a primary effect of carbidopa on the peripheral nervous system. Carbidopa has not been shown to enhance the intrinsic efficacy of levodopa.

In considering whether to give Lodosyn with Sinemet (carbidopa-levodopa) or with levodopa to patients who have nausea and/or vomiting, the physician should be aware that, while many patients may be expected to improve, some may not. Since one cannot predict which patients are likely to improve, this can only be determined by a trial of therapy. It should be further noted that in controlled trials comparing carbidopa and levodopa with levodopa alone, about half the patients with nausea and/or vomiting on levodopa alone improved spontaneously despite being retained on the same dose of levodopa during the controlled portion of the trial.

PubChem 2D Structure:

Generic Name:
carbidopa, entacapone, and levodopa

Trade Name:
Stalevo ® [Orion]

IUPAC Name:
3-(3,4-dihydroxyphenyl)-2-
hydrazinyl-2-methyl-propanoic
acid hydrate; 2-cyano-3-(5-
dihydroxyamino-3,4-dioxo-1-
cyclohexa-1,5-dienyl)-N,N-
diethyl-prop-2-enamide;
2-amino-3-(3,4-dihydroxyphenyl)-
propanoic acid

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
Carbidopa:
a-methyl-3-methoxy-4-
hydroxyphenylpropionic acid;
a-methyl-3,4-
dihydroxyphenylpropionic acid
Entacapone:
cis-entacapone;
entacapone glucuronide
Levodopa:
dopamine;
homovanillic acid

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
[PubChem]

Initial Approval:
06/11/2003

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Indications:
Stalevo (carbidopa, levodopa and entacapone) is indicated to treat patients with idiopathic Parkinson’s disease:

1. To substitute (with equivalent strength of each of the three components) for immediate-release carbidopa/levodopa and entacapone previously administered as individual products.

2. To replace immediate-release carbidopa/levodopa therapy (without entacapone) when patients experience the signs and symptoms of end-of-dose "wearing-off" (only for patients taking a total daily dose of levodopa of 600 mg or less and not experiencing dyskinesias, see DOSAGE AND ADMINISTRATION in the prescribing information).

Possible Mechanisms of Action:
Levodopa is the immediate precursor to dopamine. Entacapone is a selective, reversible catechol-O-methyltransferase (COMT) inhibitor that increases the bioavailability of levodopa (19). Entacapone does not cross the blood-brain barrier (20). Carbidopa is a peripheral aromatic L-amino acid decarboxylase (AADC) inhibitor (18). Carbidopa, which also does not cross the blood-brain barrier, is combined with levodopa to prevent its conversion to dopamine in the periphery (18).

"3D" Structure of levodopa (Requires Chime):
[Link] 

Generic Name:
carbidopa and levodopa

Trade Name:
Sinemet ® [Bristol-Myers Squibb]

IUPAC Name:
3-(3,4-dihydroxyphenyl)-2-
hydrazinyl-2-methyl-propanoic
acid; 2-amino-3-(3,4-
dihydroxyphenyl)-propanoic acid

Dosage Forms/Routes:
Tablet/oral;
Tablet (extended release)/oral

Major Metabolites:
Carbidopa:
a-methyl-3-methoxy-4-
hydroxyphenylpropionic acid;
a-methyl-3,4-
dihydroxyphenylpropionic acid
Levodopa:
dopamine;
homovanillic acid

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
[PubChem]

Initial Approval:
05/02/1975

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₉H₂₅N₃O₈

Molecular Mass:
423.417 g/mol

Possible Mechanisms of Action:
Levodopa is the immediate precursor to dopamine. Carbidopa is a peripheral aromatic L-amino acid decarboxylase (AADC) inhibitor (18). Carbidopa, which does not cross the blood-brain barrier, is combined with levodopa to prevent its conversion to dopamine in the periphery (18).

Indications:
Sinemet is indicated in the treatment of the symptoms of idiopathic Parkinson's disease (paralysis agitans), post-encephalitic parkinsonism, and symptomatic parkinsonism which may follow injury to the nervous system by carbon monoxide intoxication and/or manganese intoxication. Sinemet is indicated in these conditions to permit the administration of lower doses of levodopa with reduced nausea and vomiting, with more rapid dosage titration, with a somewhat smoother response, and with supplemental pyridoxine (vitamin B6).

In some patients a somewhat smoother antiparkinsonian effect results from therapy with Sinemet than with levodopa. However, patients with markedly irregular ("on-off") responses to levodopa have not been shown to benefit from Sinemet.

Although the administration of carbidopa permits control of parkinsonism and Parkinson's disease with much lower doses of levodopa, there is no conclusive evidence at present that this is beneficial other than in reducing nausea and vomiting, permitting more rapid titration, and providing a somewhat smoother response to levodopa.

Certain patients who responded poorly to levodopa have improved when Sinemet was substituted. This is most likely due to decreased peripheral decarboxylation of levodopa which results from administration of carbidopa rather than to a primary effect of carbidopa on the nervous system. Carbidopa has not been shown to enhance the intrinsic efficacy of levodopa in parkinsonian syndromes.

In considering whether to give Sinemet to patients already on levodopa who have nausea and/or vomiting, the practitioner should be aware that, while many patients may be expected to improve, some do not. Since one cannot predict which patients are likely to improve, this can only be determined by a trial of therapy. It should be further noted that in controlled trials comparing Sinemet with levodopa, about half of the patients with nausea and/or vomiting on levodopa improved spontaneously despite being retained on the same dose of levodopa during the controlled portion of the trial.

PubChem 2D Structure:

"3D" Structure of levodopa (Requires Chime):
[Link] 

Generic Name:
entacapone

Trade Name:
Comtan ® [Orion (marketed by Novartis)]

IUPAC Name:
2-cyano-3-(5-dihydroxyamino-
3,4-dioxo-1-cyclohexa-1,5-
dienyl)-N,N-diethyl-prop-2-
enamide

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
cis-entacapone;
entacapone glucuronide

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
[PubChem]
[PDSP K_i database]

Initial Approval:
10/19/1999

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₄H₁₅N₃O₅

Molecular Mass:
305.286 g/mol

Indications:
Comtan is indicated as an adjunct to levodopa / carbidopa to treat patients with idiopathic Parkinson’s Disease who experience the signs and symptoms of end-of-dose “wearing-off” (see CLINICAL PHARMACOLOGY: Clinical Studies in the prescribing information).

Comtan’s effectiveness has not been systematically evaluated in patients with idiopathic Parkinson’s Disease who do not experience end-of-dose “wearing-off.”

Chemical Class:
nitrocatechol

PubChem 2D Structure:

Generic Name:
pergolide mesylate

Trade Name:
Permax ® [Eli Lilly]

Common Chemical Name:
8B-[(Methylthio)methyl]-6-
propylergoline
monomethanesulfonate

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
pergolide sulfone;
pergolide sulfoxide;
despropyl pergolide;
despropyl pergolide sulfoxide

Database Search Links:
[PubMed]
[Search PubMed for
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[PDSP K_i database]

Initial Approval:
12/30/1988

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₂₀H₃₀N₂O₃S₂

Molecular Mass:
410.596 g/mol

Indications:
Permax is indicated as adjunctive treatment to levodopa/carbidopa in the management of the signs and symptoms of Parkinson’s disease.

Evidence to support the efficacy of pergolide mesylate as an antiparkinsonian adjunct was obtained in a multicenter study enrolling 376 patients with mild to moderate Parkinson’s disease who were intolerant to l-dopa/carbidopa as manifested by moderate to severe dyskinesia and/or on-off phenomena. On average, the patients evaluated had been on l-dopa/carbidopa for 3.9 years (range, 2 days to 16.8 years). The administration of pergolide mesylate permitted a 5% to 30% reduction in the daily dose of l/dopa. On average, these patients treated with pergolide mesylate maintained an equivalent or better clinical status than they exhibited at baseline.

Chemical Class:
ergot derivative

PubChem 2D Structure:

Generic Name:
pramipexole dihydrochloride

Trade Name:
Mirapex ® [Boehringer Ingelheim (marketed by Pfizer)]

IUPAC Name:
N'-propyl-4,5,6,7-
tetrahydrobenzothiazole-2,6-
diamine hydrate dihydrochloride

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
pramipexole is excreted primarily as unchanged drug

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
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[PDSP K_i database]

Initial Approval:
07/01/1997

Manufacturers:
[FDA Search]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₀H₂₁Cl₂N₃OS

Molecular Mass:
302.265 g/mol

Indications:
Mirapex tablets are indicated for the treatment of the signs and symptoms of idiopathic Parkinson’s disease.

The effectiveness of Mirapex was demonstrated in randomized, controlled trials in patients with early Parkinson’s disease who were not receiving concomitant levodopa therapy as well as in patients with advanced disease on concomitant levodopa (see CLINICAL PHARMACOLOGY - CLINICAL STUDIES at RxList).

Chemical Class:
tetrahydrobenzothiazole derivative

PubChem 2D Structure:

Generic Name:
procyclidine hydrochloride

Trade Name:
Kemadrin ® [Monarch]

IUPAC Name:
1-cyclohexyl-1-phenyl-3-
pyrrolidin-1-yl-propan-1-ol
hydrochloride

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
1-(cis-4-hydroxycyclohexyl)-1-
phenyl-3-(1-pyrrolidinyl)-1-
propanol;
1-(trans-4-hydroxycyclohexyl)-1-
phenyl-3-(1-pyrrolidinyl)-1-
propanol

Database Search Links:
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[Search PubMed for
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[PDSP K_i database]

Initial Approval:
07/27/1955

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

Empirical Formula:
C₁₉H₃₀ClNO

Molecular Mass:
323.9 g/mol

Indications:
Procyclidine is indicated in the treatment of parkinsonism including the postencephalitic, arteriosclerotic, and idiopathic types. Partial control of the parkinsonism symptoms is the usual therapeutic accomplishment. Procyclidine is usually more efficacious in the relief of rigidity than tremor; but tremor, fatigue, weakness, and sluggishness are frequently beneficially influenced. It can be substituted for all the previous medications in mild and moderate cases. For the control of more severe cases, other drugs may be added to procyclidine therapy as indications warrant.

Clinical reports indicate that procyclidine often successfully relieves the symptoms of extrapyramidal dysfunction (dystonia, dyskinesia, akathisia, and parkinsonism) which accompany the therapy of mental disorders with phenothiazine and rauwolfia compounds. In addition to minimizing the symptoms induced by tranquilizing drugs, the drug effectively controls sialorrhea resulting from neuroleptic medication. At the same time, freedom from the side effects induced by tranquilizer drugs, as provided by the administration of procyclidine, permits a more sustained treatment of the patient's mental disorder.

Chemical Class:
piperidyl derivative

PubChem 2D Structure:

Generic Name:
ropinirole hydrochloride

Trade Name:
Requip ® [GlaxoSmithKline]

IUPAC Name:
4-(2-dipropylaminoethyl)-1,3-
dihydroindol-2-one hydrochloride

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
7-hydroxy ropinirole;
N-despropyl ropinirole

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
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[PDSP K_i database]

Initial Approval:
09/19/1997

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₆H₂₅ClN₂O

Molecular Mass:
296.835 g/mol

Indications:
Ropinirole is indicated for the treatment of the signs and symptoms of idiopathic Parkinson's disease.

The effectiveness of ropinirole was demonstrated in randomized, controlled trials in patients with early Parkinson's disease who were not receiving concomitant L-dopa therapy as well as in patients with advanced disease on concomitant L-dopa (see CLINICAL PHARMACOLOGY , Clinical Trials in the prescribing information).

Ropinirole is also indicated for the treatment of moderate-to-severe primary Restless Legs Syndrome (RLS).

Chemical Class:
indolinone derivative

PubChem 2D Structure:

Generic Name:
selegiline hydrochloride

Trade Name:
Eldepryl ® [Somerset]

IUPAC Name:
N-methyl-1-phenyl-N-prop-2-
ynyl-propan-2-amine
hydrochloride

Dosage Forms/Routes:
Capsule/oral;
Tablet/oral

Major Metabolites:
N-desmethylselegiline;
L-methamphetamine;
L-amphetamine

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
[PubChem]
[PDSP K_i database]

Initial Approval:
05/15/1996

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₃H₁₈ClN

Molecular Mass:
223.741 g/mol

Indications:
Selegiline is indicated as an adjunct in the management of Parkinsonian patients being treated with levodopa/carbidopa who exhibit deterioration in the quality of their response to this therapy. There is no evidence from controlled studies that selegiline has any beneficial effect in the absence of concurrent levodopa therapy.

Evidence supporting this claim was obtained in randomized controlled clinical investigations that compared the effects of added selegiline or placebo in patients receiving levodopa/carbidopa. Selegiline was significantly superior to placebo on all three principal outcome measures employed: change from baseline in daily levodopa/carbidopa dose, the amount of 'off' time, and patient self-rating of treatment success. Beneficial effects were also observed on other measures of treatment success (e.g., measures of reduced end of dose akinesia, decreased tremor and sialorrhea, improved speech and dressing ability and improved overall disability as assessed by walking and comparison to previous state).

Chemical Class:
levorotatory acetylenic derivative of phenethylamine

PubChem 2D Structure:

"3D" Structure (Requires Chime):
[Link]

Generic Name:
tolcapone

Trade Name:
Tasmar ® [Valeant]

IUPAC Name:
2-dihydroxyamino-4-(4-
methylbenzoyl)-cyclohexa-2,4-
diene-1,6-dione

Dosage Forms/Routes:
Tablet/oral

Major Metabolites:
3-O-beta, d-glucuronide conjugate of tolcapone;
3-O-methyltolcapone

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
[PubChem]
[PDSP K_i database]

Initial Approval:
01/29/1998

Manufacturers:
[FDA Search]

Prescribing Information:
[Link]

RxList:
[Link]

Epocrates:
[Link]

Empirical Formula:
C₁₄H₁₁NO₅

Molecular Mass:
273.241 g/mol

Indications:
Tolcapone is indicated as an adjunct to levodopa and carbidopa for the treatment of the signs and symptoms of idiopathic Parkinson’s disease. Because of the risk of potentially fatal, acute fulminant liver failure, tolcapone should ordinarily be used in patients with Parkinson’s disease on l-dopa/carbidopa who are experiencing symptom fluctuations and are not responding satisfactorily to or are not appropriate candidates for other adjunctive therapies. Because of the risk of liver injury and because tolcapone, when it is effective, provides an observable symptomatic benefit, the patient who fails to show substantial clinical benefit within 3 weeks of initiation of treatment, should be withdrawn from t olcapone.

The effectiveness of tolcapone was demonstrated in randomized controlled trials in patients receiving concomitant levodopa therapy with carbidopa or another aromatic amino acid decarboxylase inhibitor who experienced end of dose wearing-off phenomena as well as in patients who did not experience such phenomena (see CLINICAL PHARMACOLOGY: Clinical Studies in the prescribing information).

Chemical Class:
nitrocatechol

PubChem 2D Structure:

Generic Name:
trihexyphenidyl hydrochloride

IUPAC Name:
1-cyclohexyl-1-phenyl-3-(1-
piperidyl)propan-1-ol
hydrochloride

Dosage Forms/Routes:
Tablet/oral;
Elixir/oral

Major Metabolite:
hydroxylated metabolite of trihexyphenidyl

Database Search Links:
[PubMed]
[Search PubMed for
Randomized Controlled Trials]
[PubChem]
[PDSP K_i database]

Initial Approval:
05/13/1949

Manufacturers:
[FDA Search]

Prescribing Information:
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RxList:
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Epocrates:
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Empirical Formula:
C₂₀H₃₂ClNO

Molecular Mass:
337.927 g/mol

Indications:
Trihexyphenidyl is indicated as an adjunct in the treatment of all forms of parkinsonism (postencephalitic, arteriosclerotic and idiopathic). It is often useful as adjuvant therapy when treating these forms of parkinsonism with levodopa. Additionally, it is indicated for the control of extrapyramidal disorders caused by central nervous system drugs such as the dibenzoxazepines, phenothiazines, thioxanthenes, and butyrophenones.

Chemical Class:
piperidyl derivative

PubChem 2D Structure: