Tasmar - Tolcapone

Tasmar (Tolcapone). Valeant Fbarmaceuticals Ltd. UK Summary of product characteristics, August 2006. 

A newer classification of antiparkinson drugs is the catechol-O-methyltransferase (COMT) inhibitors. Examples of the COMT inhibitors are entacapone (Comtan) and tolcapone (Tasmar). 

Tolcapone (Tasmar ) Peripherally blocks COMT metabolism of DA some central activity Start with 1 00 mg with first Sinemet dose once daily if symptoms continue, increase to 2 and then 3 times daily, then to 200 mg each dose usual MD is 1 00 three times daily to minimize risk of side-effects... 

Tolcapone (Tasmar) and entacapone (Comtan) are used only in conjunction with carbidopa/L-dopa to prevent the peripheral conversion of L-dopa to dopamine (increasing the area under the curve of L-dopa by approximately 35%). Thus, on time is increased by about 1 hour. These agents significantly decrease off time and decrease L-dopa requirements. Concomitant use of nonselective MAO inhibitors should be avoided to prevent inhibition of the pathways for normal catecholamine metabolism. 

Tolcapone (Tasmar) Parkinson s disease Hepatic toxicity 1998 [59]... 

A final pharmacological strategy for treatment of Parkinson s disease comes from enzyme inhibition. This was initally done with an MAO inhibitor, L-deprenyl (selegiline, Eldepryl), but more recent drugs have become available that are COMT inhibitors. L-Deprenyl is an inhibitor of MAOB, which is the form of MAO selective to dopamine. Thus, it may increase the amount of available dopamine for release. Second, it may protect dopamine neurons by reducing the oxidative stress concomitant with dopamine metabolism (Olanow 1997). Third, L-deprenyl is metabolized into amphetamine and methamphetamine, which may contribute to their antiparkinsonian effects. Unlike other treatments for Parkinson s disease, L-deprenyl seems to slow the progression of the disease. Tolcapone (Tasmar) is a COMT inhibitor, which prevents extracellular breakdown of dopamine. 

Tolcapone (Tasmar) [Antiparkinsonion Agent/COMT Inhibitor]... 

The two COMT inhibitors in clinical use are tol-capone (Tasmar) and entacapone fComtan). They are used in combination with levodopa-carbidopa. In patients with motor fluctuations, they increase the on time. Adverse effects are similar to those observed with levodopa-carbidopa alone. Tolcapone therapy can cause fatal hepatotoxicity and so should be used only in patients who do not respond to other therapies. Patients taking tolcapone require close monitoring of liver enzymes for signs of hepatic changes. 

Olanow CW. Tolcapone and hepatotoxic effects. Tasmar Advisory Panel. Arch Neurol 2000 57(2) 263-7. 

Example Tolcapone (Tasmar) Route PO Pregnancy Pharmacokinetic PB UK category UK ... 

Finally, MAO-B inhibitors such as selegiline and the COMT inhibitors tolcapone (Tasmar, Roche) and entacapone (Comtan, Novartis) extend the action of L-dopa. Entacapone is now available in fixed-dose combinations with carbidopa/L-dopa as well (Stalevo, Novartis). 

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