Levodopa/Carbidopa for Parkinson's Disease

Overview
Together, Levodopa and Carbidopa form a combination prescription drug originally approved by the Food and Drug Administration (FDA) in 1975. Levodopa/Carbidopa is used to treat motor symptoms of Parkinsonism caused by Parkinson’s Disease, encephalitis, or exposure to carbon monoxide or manganese. Levodopa/Carbidopa may provide some benefit for those with Progressive Supranuclear Palsy, Vascular Parkinsonism, Multiple System Atrophy, and Corticobasal Degeneration. Levodopa/Carbidopa is sold under the brand names Sinemet, Parcopa, and Duopa.

Levodopa/Carbidopa is not appropriate for people with undiagnosed skin lesions, narrow-angle glaucoma, or a history of melanoma. Levodopa/Carbidopa is not suitable for use in people who have previously shown hypersensitivity to Levodopa or Carbidopa. Levodopa/Carbidopa must be used with caution in people with wide-angle glaucoma, diabetes, asthma, emphysema, mental illness, or problems with the heart, kidneys, liver, lungs, or blood vessels. Levodopa/Carbidopa may not be appropriate for women who are pregnant or breastfeeding.

Levodopa/Carbidopa is a combination drug. Levodopa is the precursor molecule to the neurotransmitter Dopamine. Levodopa is believed to treat Parkinsonian motor symptoms by increasing the concentration of Dopamine in the brain. Carbidopa is a molecule that inhibits the breakdown of Levodopa into Dopamine before it reaches the brain. Carbidopa is believed to work by increasing the amount of Levodopa that reaches the brain, making Levodopa effective at significantly lower doses.

Some medications are available both as generic and branded products. Although generic and branded formulations of a drug contain the same active ingredients at the same concentrations, your body may react differently to different formulations. Check with your doctor before switching between drug brands or between generic and branded drugs.

How do I take it?
Do not begin taking Levodopa/Carbidopa within two weeks of taking a monoamine oxidase (MAO) inhibitor. If you are switching from Levodopa alone to Levodopa/Carbidopa, wait 12 hours after your final dose of Levodopa before taking your first dose of Levodopa/Carbidopa.

While you are on Levodopa/Carbidopa, your doctor will order regular blood tests to monitor your liver, kidney, and heart function. Examine your skin regularly for changes and visit your dermatologist regularly to check for signs of melanoma. If you have wide-angle glaucoma, make sure your ophthalmologist regularly monitors your intraocular pressure.

Levodopa/Carbidopa may be taken orally as a tablet or disintegrating tablet, or as an infusion into your small intestine. Orally, Levodopa/Carbidopa is taken three or four times a day. Oral Levodopa/Carbidopa should be taken at the same times each day. Take oral formulations of Levodopa/Carbidopa 30 minutes to one hour before eating a meal to encourage efficient absorption. If you experience nausea after taking Levodopa/Carbidopa orally, you may take it with a small amount of carbohydrate food, such as a plain cracker. Ginger tea may help calm your stomach when taking Levodopa/Carbidopa.

To receive Levodopa/Carbidopa as an intestinal infusion, you will need to receive minor surgery to create a hole, known as a stoma, in your abdomen. The surgeon will fit a small tube with a pump into the hole. You will learn how to plug small cassettes containing medication into the pump, which infuses Levodopa/Carbidopa continually into your system.

Avoid taking iron supplements or eating a diet high in protein or fat while on Levodopa/Carbidopa. Consuming large amounts of these nutrients can interfere with the body’s absorption of Levodopa/Carbidopa.

Avoid driving or operating machinery until you are certain you understand how Levodopa/Carbidopa affects you.

You may experience withdrawal symptoms if you stop taking Levodopa/Carbidopa suddenly. If you decide to stop taking Levodopa/Carbidopa ask your doctor for a plan to decrease your dosage gradually.

Always follow your doctor’s instructions exactly when taking Levodopa/Carbidopa.

Results
Levodopa/Carbidopa is considered to be the most effective treatment for the motor symptoms of Parkinson’s Disease and some types of Parkinsonism.

Side effects
Common side effects of Levodopa/Carbidopa include nausea, vomiting, diarrhea, constipation, dizziness, drowsiness, nervousness, headaches, confusion, memory problems, nightmares, problems sleeping, sweating, loss of appetite, or changes in the sense of taste. Tell your doctor if these side effects become worse. Levodopa/Carbidopa may cause your urine, sweat, or saliva to turn dark colors, which can stain clothes.

Due to the method of its delivery, Levodopa/Carbidopa intestinal infusion can cause gastrointestinal complications, some of which can become serious or even fatal. Gastrointestinal complications may include wound infection, intestinal perforation, paralysis (ileus), bleeding, or circulation problems (ischemia), pancreatitis, peritonitis, and ulcer or erosion around the tube.

Inform your doctor immediately if you experience a fast, pounding heartbeat, hallucinations, suicidal thoughts, depression, increased urge to have sex or gamble, stools containing blood or a tarry substance, vomit containing blood or a substance resembling coffee grounds, hoarseness, or abnormal body movements while taking Levodopa/Carbidopa.

Many drugs can cause allergic reactions that in the most serious cases, can result in death. Seek immediate medical help if you experience signs of a severe allergic reaction such as hives, difficulty breathing, or swelling in the face, throat, eyes, lips or tongue.