Duodopa or Duopa, also known as levodopa/carbidopa intestinal gel (LCIG), is a formulation of levodopa and carbidopa developed by AbbVie to treat motor fluctuations. It is administered over 16 hours via a tube surgically inserted into the small intestine of people with advanced Parkinson’s disease.

Duodopa was approved by the European Medicines Agency (EMA) in 2005. The U.S. Food and Drug Administration (FDA) approved the treatment, under the brand name Duopa, in January 2015.

How Duodopa/Duopa works

Parkinson’s disease is characterized by the loss of the neurotransmitter dopamine — a chemical messenger that allows for the transmission of electric signals between nerve cells and from the brain to various muscles in the body.

Dopamine cannot be directly administered because it cannot cross the blood-brain barrier, a semipermeable membrane that protects the brain and spinal cord from insults, like viruses, that can be carried in circulating blood.

Levodopa is the chemical building block from which dopamine is synthesized in the body. Levodopa can cross the blood-brain barrier easily and be converted to dopamine in the brain, easing muscle stiffness and involuntary movements.

Carbidopa is an agent that helps prevent the breakdown of levodopa so more of it is available to the brain to make dopamine. This reduces the amount of levodopa that needs to be administered, helping to limit side effects of levodopa treatment that can include nausea and vomiting.

Duodopa/Duopa is administered as a gel suspension through a tube that is surgically inserted into the small intestine, this way bypassing the stomach and allowing levodopa to be more quickly absorbed.

A pump helps deliver the required dosage continuously through the tube, ensuring a steady concentration of the therapy is available in the blood.

Duodopa/Duopa in trials for Parkinson’s

Two studies found that Duodopa/Duopa can lower the duration of off episodes in people with advanced Parkinson’s disease. So-called off episodes are periods in which the medication stops working and symptoms return before another dose can be taken. One study in particular found that controlling motor symptom fluctuations was associated with meaningful improvements in patients’ quality of life.

Duodopa/Duopa was also found to reduce impulse control disorders — such as compulsive gambling, buying or sexual behavior — in patients with advanced Parkinson’s. These conditions are known to be related to the use of dopamine replacement agents. Researchers also reported that the treatment significantly eased patients’ psychosis, improved sleep quality and improved social interactions.

A Phase 3 study (NCT02799381) evaluated the effectiveness of LCIG in lessening dyskinesia — uncontrolled, involuntary movements — compared to an optimized antiparkinsonian treatment. Trial findings showed Duodopa/Duopa significantly lessened dyskinesia, and improved health-related quality of life compared with the other medications.

A Phase 4 study (NCT00141518) in Europe, completed in 2011, investigated the cost-effectiveness of Duodopa’s use by advanced Parkinson’s patients. Its researchers reported that Duodopa is a more cost-effective treatment option than standard-of-care therapy in this patient group.

A multicenter and observational study (NCT02289729) also found that Duodopa eased the disease’s motor and non-motor symptoms and improved well-being and quality of life in people with advanced disease that was not well controlled with conventional treatments.

An observational study (NCT02611713) evaluated Duodopa/Duopa’s safety and effectiveness over the long term (three years) in adults with advanced Parkinson’s disease. Its interim data found safety and effectiveness in reducing motor and non-motor symptoms and improving quality of life over two years of use, with a significant lessening in off time beginning three months after the start of treatment. Gastrointestinal complaints were among the most common adverse events.

An ongoing Phase 4 study (NCT02480803) in the Netherlands is comparing the cost-effectiveness of Duodopa with deep brain stimulation, a surgical treatment to stimulate targeted regions in the brain with electrical impulses.

Other information

The maximum recommended daily dose of Duodopa/Duopa is 2000 milligrams (mg) of levodopa administered over 16 hours, with the total daily dose titrated based on an individual patient’s clinical response.

Duodopa/Duopa use can cause serious side effects, including hallucinations or confusion, falling asleep during normal activities, low blood pressure, depression or suicidal thoughts, and dyskinesia. Its most common side effects can include complications from the device’s insertion, nausea, depression, swelling (edema) in the hands and feet, hypertension, upper respiratory tract infections, throat (oropharyngeal) pain, and irritation at the incision site.

Duodopa/Duopa is contraindicated in patients who are taking nonselective monoamine oxidase (MAO) inhibitors.

More information can be found on the therapy’s label.


Last updated: Dec. 13, 2021, by Teresa Carvalho MSc


Parkinson’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.


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