Medical Usage of L-DOPA

  • Author:Hubei Ocean Biotech Co,.LTd
  • Release on :2016-05-31
L-DOPA crosses the protective blood–brain barrier, whereas dopamine itself cannot. Thus, L-DOPA is used to increase dopamine concentrations in the treatment of Parkinson's disease and dopamine-responsive dystonia. This treatment was made practical and proven clinically by George Cotzias and his coworkers, for which they won the 1969 Lasker Prize. Once L-DOPA has entered the central nervous system, it is converted into dopamine by the enzyme aromatic L-amino acid decarboxylase, also known as DOPA decarboxylase. Pyridoxal phosphate (vitamin B6) is a required cofactor in this reaction, and may occasionally be administered along with L-DOPA, usually in the form of pyridoxine.

Besides the central nervous system, L-DOPA is also converted into dopamine from within the peripheral nervous system. Excessive peripheral dopamine signaling causes many of the adverse side effects seen with sole L-DOPA administration. To bypass these effects, it is standard clinical practice to coadminister (with L-DOPA) a peripheral DOPA decarboxylase inhibitor (DDCI) such as carbidopa (medicines containing carbidopa, either alone or in combination with L-DOPA, are branded as Lodosyn (Aton Pharma) Sinemet (Merck Sharp & Dohme Limited), Pharmacopa (Jazz Pharmaceuticals), Atamet (UCB), and Stalevo (Orion Corporation) or with a benserazide (combination medicines are branded Madopar or Prolopa), to prevent the peripheral synthesis of dopamine from L-DOPA. Coadministration of pyridoxine without a DDCI accelerates the peripheral decarboxylation of L-DOPA to such an extent that it negates the effects of L-DOPA administration, a phenomenon that historically caused great confusion.

In addition, L-DOPA, co-administered with a peripheral DDCI, has been investigated as a potential treatment for restless leg syndrome. However, studies have demonstrated "no clear picture of reduced symptoms".

Countless suppliers have appeared in this market.How to find a honest and reliable supplier as a long-term partner?It is really a considerable problem for many purchasers,especially for whom do purchase work for the first time. 

How to choose a quality and trustable L-DOPA supplier?HBOCEAN,as a professional supplier of pharmaceutical raw materials within 10-year experience,always persist in the management purpose of "Quality First and Credit Supremacy" and the management ideas of "Honesty and Win-Win".Nowadays,we have gained good reputation at domestic and abroad market. Don't be hesitated to contact us.