How Does Carbidopa-Levodopa CR Work?Carbidopa-levodopa CR contains two different active ingredients, levodopa and carbidopa. The levodopa is the "real" ingredient in carbidopa-levodopa CR that works for Parkinson's disease. The carbidopa does not have any direct effects on Parkinson's disease when used alone, but it does help to make the levodopa more effective.
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, as dopamine cannot cross the blood-brain barrier to reach the brain. Levodopa is a precursor of dopamine, which means that the body can use levodopa 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 that often accompany levodopa therapy. Carbidopa also reduces the amount of levodopa needed for Parkinson's disease treatment.
When and How to Take Carbidopa-Levodopa CRSome general considerations for when and how to take carbidopa-levodopa CR include the following:
- The medication comes in extended-release tablet form. It is taken by mouth usually two or three times a day.
- Do not crush or chew carbidopa-levodopa CR tablets. However, carbidopa-levodopa CR 50-200 mg tablets (but not 25-100 mg tablets) may be broken in half along the score line if necessary.
- The protein in food can decrease the absorption of carbidopa-levodopa CR into the body. Some healthcare providers recommend taking carbidopa-levodopa CR on an empty stomach (or with a low-protein diet).
- Make sure to take carbidopa-levodopa CR at the same times each day to maintain an even level of the medication in your blood.
- For the medication to work properly, it must be taken as prescribed. Carbidopa-levodopa CR will not work if you stop taking it. Do not suddenly stop taking the drug without first talking to your healthcare provider.