What Is Carbidopa?

Carbidopa is a medication that is primarily used in treating the symptoms of Parkinson’s disease, a degenerative condition that affects the central nervous system and causes difficulties controlling movements and impairs muscle function. It is thought to perhaps be the result of abnormally low levels of dopamine, a chemical in the brain that is responsible for a variety of functions, including controlling the body’s movement. The medication is typically only effective at treating Parkinson’s disease when it is combined with another drug known as levodopa.

Levodopa and carbidopa work together at treating the symptoms of Parkinson’s disease in a process. Since Parkinson’s disease is thought to be the result of low levels of dopamine, levodopa may help decrease Parkinson’s disease symptoms, such as tremors, stiffness, and muscle spasms, by increasing the amounts of dopamine in the body. When levopoda is taken, it turns into dopamine; however, the medication risks being metabolized by the body in the bloodstream before it can reach the brain as dopamine and effectively treat Parkinson’s disease symptoms. Carbidopa may help slow down the metabolizing of levopoda so that it has time to be released as dopamine in the brain, rather than being absorbed into the bloodstream.

Although this combination drug therapy may be helpful at reducing some of the symptoms of Parkinson’s disease, carbidopa may also cause certain side effects when used with levopoda. The most common side effects include dizziness, difficulty sleeping, blurred vision, nausea, trembling of the hands, nightmares, and discoloration of the urine. These effects are generally not considered serious and do not usually require medical attention unless they become more severe over time. Serious side effects, such as difficulty breathing, abnormal heartbeat, thoughts of suicide, and seizures, may also occur rarely and typically need emergency medical care to prevent potentially fatal complications. People who are on this type of medication therapy for Parkinson’s disease may also be at a higher risk of developing melanoma, a type of skin cancer, and may be advised to be diligent on protecting their skin from the sun and having a dermatologist monitor the appearance of any moles or freckles to ensure they aren’t cancerous.

Carbidopa is generally available as a pill to be taken orally. It is usually administered at the same time as levopoda, approximately three days each day. Overdosing on these medications can result in vomiting, diarrhea, hallucinations, and loss of consciousness, so doctors will typically recommend that if a person misses a dose, he or she simply skips it rather than trying to double up on the medication to make up for the skipped dose. If a person is suspected of overdosing on the medication, immediate medical attention is usually required.