Carbidopa

Generic name: carbidopa
Brand name: Lodosyn
Dosage form: oral tablet (25 mg)
Drug class: Dopaminergic antiparkinsonism agents

Medically reviewed by  A Ras MD.

What is carbidopa?

Carbidopa is a prescription medicine that is used to treat Parkinson’s disease. It is used to treat signs like Parkinson’s disease caused by other health problems. Carbidopa may be given to you for other reasons.

Description

Carbidopa and levodopa extended-release tablets are an extended-release combination of carbidopa and levodopa for the treatment of Parkinson’s disease and syndrome.

Carbidopa, an inhibitor of aromatic amino acid decarboxylation, is a white, crystalline compound, slightly soluble in water, with a molecular weight of 244.24. It is designated chemically as (-)-L-α-hydrazino-α-methyl-β-(3,4-dihydroxybenzene) propanoic acid monohydrate. Its empirical formula is C10H14N2O4•H2O and its structural formula is:

Image from Drug Label Content

 

Tablet content is expressed in terms of anhydrous carbidopa, which has a molecular weight of 226.23.

Levodopa, an aromatic amino acid, is a white, crystalline compound, slightly soluble in water, with a molecular weight of 197.2. It is designated chemically as (-)-L-α-amino-β-(3,4-dihydroxybenzene) propanoic acid. Its empirical formula is C9H11NO4 and its structural formula is:

 

Image from Drug Label Content

Carbidopa and levodopa extended-release tablets are supplied as extended-release tablets containing 50 mg of carbidopa and 200 mg of levodopa. Inactive ingredients: colloidal silicon dioxide, D&C Yellow No. 10, FD&C Red No. 3, fumaric acid, hypromellose, and sodium stearyl fumarate.

The carbidopa and levodopa extended-release tablet is a polymeric-based drug delivery system that controls the release of carbidopa and levodopa as it slowly erodes. The 50 mg/200 mg half-tablet (bisect) will facilitate a 25 mg/100 mg tablet dose.

Before taking carbidopa, tell your doctor:

For all patients taking carbidopa:

  • If you are allergic to carbidopa; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have glaucoma.
  • If you have taken certain drugs for depression or Parkinson’s disease in the last 14 days. This includes isocarboxazid, phenelzine, tranylcypromine, selegiline, or rasagiline. Very high blood pressure may happen.
  • If you are taking another drug that has the same drug in it.
  • If you are breast-feeding or plan to breast-feed.

Children:

  • If the patient is a child. Do not give carbidopa to a child.

This is not a list of all drugs or health problems that interact with carbidopa.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take carbidopa with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take carbidopa?

  • Tell all of your health care providers that you take carbidopa. This includes your doctors, nurses, pharmacists, and dentists.
  • Avoid driving and doing other tasks or actions that call for you to be alert until you see how carbidopa affects you.
  • To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
  • Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take carbidopa.
  • If you have high blood sugar (diabetes), talk with your doctor about which glucose tests are best to use.
  • This medicine may “wear off” as the time for your next dose gets closer. Tell your doctor if this happens and it bothers you.
  • A dark color (red, brown, or black) may show up in your saliva, urine, or sweat. This is not harmful but may discolor your clothes.
  • It may take a few months to see the full effect.
  • This medicine is used with a drug called levodopa.
  • Some people have fallen asleep during activities like driving, eating, or talking. Some people did not feel sleepy and felt alert right before falling asleep. This has happened up to 1 year after carbidopa was started. If you fall asleep during activities, do not drive or do other tasks or actions that call for you to be alert while you take carbidopa. Call your doctor right away if this happens or you feel very sleepy.
  • The chance of a type of skin cancer called melanoma may be raised in people with Parkinson’s disease. It is not known if carbidopa may also raise the chance. Have skin exams while you take carbidopa. Talk with your doctor.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using carbidopa while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is carbidopa best taken?

Use carbidopa as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Diets high in protein, fat, or calories may lower how well your body absorbs carbidopa; tell your doctor if you have a diet like this or if you will be changing your diet. Talk with your doctor.
  • If you take an iron product or a multivitamin that has iron, ask your doctor or pharmacist how to take it with carbidopa. Iron may lower how well your body is able to absorb carbidopa.
  • Do not stop taking carbidopa all of a sudden or lower your dose without talking to your doctor. Side effects may happen.
  • Take carbidopa at the same time of day.
  • Keep taking carbidopa even when you are not having symptoms.
  • Keep a diary of your signs.
  • Keep taking carbidopa as you have been told by your doctor or other health care provider, even if you feel well.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

What are the side effects of carbidopa that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of low mood (depression), thoughts of killing yourself, nervousness, emotional ups and downs, thinking that is not normal, anxiety, or lack of interest in life.
  • Signs of high or low blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
  • Change in the way you act.
  • Hallucinations (seeing or hearing things that are not there).
  • Feeling confused.
  • Strong urges that are hard to control (such as eating, gambling, sex, or spending money).
  • Throwing up blood or throw up that looks like coffee grounds.
  • Black, tarry, or bloody stools.
  • Belly pain.
  • A burning, numbness, or tingling feeling that is not normal.
  • Any unexplained bruising or bleeding.
  • Chest pain or pressure.
  • A heartbeat that does not feel normal.
  • Fever or chills.
  • Sore throat.
  • A skin lump or growth.
  • Change in color or size of a mole.
  • Change in eyesight, eye pain, or very bad eye irritation.
  • Trouble controlling body movements that is new or worse.
  • Grinding of teeth.
  • Shortness of breath.
  • Feeling very tired or weak.
  • Swelling in the arms or legs.
  • A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.

What are some other side effects of carbidopa?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Dizziness.
  • Headache.
  • Dry mouth.
  • Feeling sleepy.
  • Not able to sleep.
  • Upset stomach or throwing up.
  • Change in taste.
  • Constipation.
  • Diarrhea.
  • Not hungry.
  • Strange or odd dreams.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out carbidopa?

  • Store at room temperature.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

 

Label

PACKAGE LABEL.PRINCIPAL DISPLAY PANEL

  • NDC 0228-2540-10
  • Carbidopa and Levodopa Tablets, USP
  • 25 mg/ 250 mg
  • Rx only
  • 100 Tablets
Container Label 25 mg/250 mg

SRC: NLM .