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TASMAR ALERT ! (from Jan-Feb issue) Tasmar brand of tolcapone, the most recently F.D.A. approved drug for treating Parkinson's disease, has caused some severe side effects, in particular a very rapid inflammation of the liver which is known to have resulted in at least three deaths. Some say that the death count may be understated since many people who have Parkinson's and die are not autopsied. It is known that there were many non-fatal cases of liver inflammation among people who took Tasmar. The news of the problem with Tasmar was made public by Hoffman-LaRoche [Roche Laboratories,Inc.], the maker of Tasmar, November 16, 1998, the day the November Parkinson's Newsletter was printed. The November Parkinson's Newsletter did not include Tasmar in its listing of Parkinson's drugs, since there had been rumors about severe Tasmar side effects. Tasmar is the only COMT inhibitor F.D.A. approved in the United States. Roche Laboratories sent warning notices to neurologists, the most likely prescribers of the product. The APDA sent notices to its chapter presidents. There were many notices posted on the Internet. The product was withdrawn from most countries in Europe. Tasmar is still available in the U.S., but many prescribing neurologists, including the Parkinson's Disease Clinic at Johns Hopkins, are limiting Tasmar prescriptions only to patients for whom other drugs do not work, who sign a waiver of liability recognizing the danger in Tasmar, and get a liver function test every two weeks. Tasmar is still available in at least some local pharmacies. On January 14, I checked with Super G Deep Discount Drug in Salisbury to see if they still carried Tasmar. They had received no notice of any problem with Tasmar and have it in stock at $217.69 per 100 for the 100 mg caplets and at $235.47 per 100 for the 200 mg caplets. Tasmar has been a very useful drug for some PD patients. According to theory, Tasmar blocks the breakdown of levodopa (the active ingredient in Sinemet) by catechol-O-methyl transferase, a natural and normally useful enzyme, found in all humans, which has an affinity for levodopa. If this is the actual situation, Tasmar could be replaced by simply taking a little more Sinemet. The benefits reported by many users indicate that it may be doing more. One European group questioned the wisdom of using Tasmar earlier, claiming that a COMT inhibitor could hasten neuronal cell death in the brain, but this was not widely believed. I have been taking another COMT inhibitor, entacapone from Orion Farma of Finland, for several years as a participant in its drug trials. Entacapone is expected to be sold as Comtan in the U.S. after receiving F.D.A. approval some time in 1999. No liver problems have been reported with entacapone, but the Tasmar scare may delay or halt approval. The neurologist in charge of my testing of entacapone said she thought Tasmar was a more effective product than entacapone. There is one major difference between entacapone and Tasmar. Tasmar can cross the blood/brain barrier, providing more complete protection for the levodopa. Entacapone does not cross the blood/brain barrier. Carbidopa, the decarboxylase enzyme inhibitor and first number in describing Sinemet strength, also does not cross the blood/brain barrier. Once the levodopa is converted to dopamine, Eldepryl, [also known as Deprenyl, Jumex, or seligeline] which also crosses the blood/brain barrier, can be used to slow the monamine oxidase enzyme's attack on dopamine. Tasmar provides some protection for the levodopa between the time it crosses the blood/brain barrier and the time it is converted to dopamine in the brain. Entacapone does not provide this protection. Tasmar now is now recommended only for those patents who are not able to get satisfactory relief from the symptoms of PD from other drugs. There is no other product providing protection for the levodopa after it has crossed into the brain. The general feeling of the experts I have talked with is that Tasmar should be used as a last resort, only when nothing else works. Only three known deaths out of the many taking the product may mean that the danger is over stated. Will Johnnston A.P.D.A. DelMarVA Chapter Pres. 4049 Oakland School Road Salisbury MD 21804 USA 410-543-0110