Description

Levodopa is used to treat the stiffness, tremors, spasms, and poor muscle control of Parkinson's disease. Levodopa is also used to treat these same muscular conditions when they are caused by drugs such as chlorpromazine (Thorazine), fluphenazine (Prolixin), perphenazine (Trilafon), and others.

The gold standard of present therapy is the drug levodopa (also called L-dopa). L-Dopa (from the full name L*3, *-dihydroxyphenylalanine) is a neutral amino acid found naturally in plants and animals. After oral ingestion, it is absorbed in the small intestine. Absorption can be delayed by meals and increased gastric acidity. Absorbed levodopa is not bound to plasma protein. Nerve cells can use levodopa to make dopamine and replenish the brain's dwindling supply. Dopamine cannot be given directly because it doesn't cross the blood-brain barrier, the elaborate meshwork of fine blood vessels and cells that filters blood reaching the brain. Levodopa crosses the blood-brain barrier by way of the large neutral amino acid carrier transport system.

Levodopa COA:

1) Appearance: White or slightly cream crystalline powder, odorless
2) Identification: I. R: Positive
3) Solubility: Meets the requirements
4) pH: 4.5 ~ 7.0
5) Color of solution: Meets the requirements
6) Organic volatile impurity: Meets the requirements
7) Light absorption: **7 ~ **7o
8) Optical rotation (BP***2): *1.*7 ~ *1.*4o
9) Specific rotation (USP*4): ***0 ~ ***7o
*0) Heavy metals (BP***2): *0ppm max., USP*4 *0ppm max.
*1) Related substances (BP***2): Meets the requirements
*2) *-(3, 4, *-Trihydroxyphenyl) alanine (USP*4): 0.1% max.
*3) *-Methoxytyrosine (USP*4): 0.5% max.
*4) Loss on drying: 1.0% max.
*5) Residue on ignition: 0.*0% max.
*6) Residual solvent: Ethanol: 1.0% max.
*7) Assay (on dry basis): *9.0~**1.0%