Lodosyn is a medication licensed to treat Parkinson's disease and Parkinson-like symptoms due to other causes. It is always used in combination with levodopa products, since it has no activity against Parkinson's when used alone. Lodosyn comes in tablet form and is available by prescription. Common side effects (when used with levodopa) include nausea, vomiting, and involuntary movements.
Lodosyn® (carbidopa) is a prescription medication used to treat Parkinson's disease. It is also approved to treat parkinsonism (Parkinson-like symptoms) due to encephalitis (inflammation or infection of the brain), manganese poisoning, or carbon monoxide poisoning. Lodosyn is always used in combination with levodopa products (Sinemet®, Sinemet® CR, Parcopa®, or Stalevo®), as it does not have any activity for treating Parkinson's disease when used alone.
Lodosyn is made by Merck & Co., Inc. and marketed by Bristol-Myers Squibb Company.
Dopamine deficiency (caused by a loss of dopamine-producing cells) in certain parts of the brain may be responsible for many of the symptoms of Parkinson's disease. Although it would make sense to give dopamine to help treat Parkinson's, this does not work, since dopamine cannot cross the blood-brain barrier to reach the brain. Levodopa is a precursor of dopamine, which means that the body can use it to make dopamine. Unlike dopamine, levodopa crosses the blood-brain barrier.
Levodopa is almost always given in combination with carbidopa. Carbidopa delays the conversion of levodopa into dopamine until it reaches the brain, preventing or diminishing some of the side effects (especially nausea and vomiting) that often accompany levodopa therapy. Carbidopa also reduces the amount of levodopa needed for Parkinson's disease treatment. It is important to understand that carbidopa has no effects on Parkinson's disease when used without levodopa.
Although most people take carbidopa as a combination product, in rare cases, some people need to take additional carbidopa. In such cases, Lodosyn can be helpful by increasing the carbidopa dose, without increasing the levodopa dose.