Levodopa

What is levodopa?

Levodopa is a medication used to treat Parkinson's disease. Parkinson's disease is associated with low levels of a chemical called dopamine (doe PA meen) in the brain. Levodopa is turned into dopamine in the body and therefore increases levels of this chemical.

Levodopa is used to treat the stiffness, tremors, spasms, and poor muscle control of Parkinson's disease. Levodopa is also used to treat these same muscular conditions when they are caused by drugs such as chlorpromazine (Thorazine), fluphenazine (Prolixin), perphenazine (Trilafon), and others.

Levodopa may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about levodopa?

Contact your doctor immediately if you experience uncontrollable movements of the face, eyelids, mouth, tongue, neck, arms, hands, or legs; severe or persistent nausea or vomiting; an irregular heartbeat or fluttering in the chest; or unusual changes in mood or behavior.

What should I discuss with my healthcare provider before taking levodopa?

Do not take levodopa if you have taken a monoamine oxidase inhibitor (MAOI), such as isocarboxazid (Marplan), tranylcypromine (Parnate), or phenelzine (Nardil) withinin the past 2 weeks. Do not take levodopa without first talking to your doctor if you have

• narrow-angle glaucoma (angle closure glaucoma), or

• malignant melanoma (a type of skin cancer).

Before taking this medication, tell your doctor if you have

• any kind of heart disease, including high blood pressure, arteriosclerosis, hardening of the arteries, a previous heart attack, or an irregular heartbeat;

• respiratory disease, including asthma and chronic obstructive pulmonary disease (COPD);

• liver disease;
• kidney disease;

• an endocrine (hormonal) disease;

• a stomach or intestinal ulcer;

• wide-angle glaucoma; or

• depression or any other psychiatric disorder.

You may need a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

How should I take levodopa?

Take levodopa exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

It is important to take levodopa regularly to get the most benefit.

It may be several weeks or months before the benefits of levodopa are seen. Do not stop taking levodopa without first talking to your doctor.

Your doctor may want you to have blood tests or other medical evaluations during treatment with levodopa to monitor progress and side effects.

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and only take the next regularly scheduled dose. Do not take a double dose of this medication.

What happens if I overdose?

Seek emergency medical attention if an overdose is suspected.

Symptoms of a levodopa overdose include nausea, diarrhea, vomiting, weakness, fainting, confusion, hallucinations, muscle twitching, and agitation.

What should I avoid while taking levodopa?

Use caution when driving, operating machinery, or performing other hazardous activities. Levodopa may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Avoid vitamin products that contain vitamin B6 (pyridoxine). This vitamin may reduce the effectiveness of levodopa.

Levodopa side effects

If you experience any of the following serious side effects, stop taking levodopa and seek emergency medical attention or contact your doctor immediately:

• an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);

• uncontrolled movements of a part of the body;

• seizures;

• persistent nausea, vomiting, or diarrhea;

• an irregular heartbeat or fluttering in the chest;

• unusual changes in mood or behavior; or

• depression or suicidal thoughts.

Other, less serious side effects may be more likely to occur. Continue to take levodopa and talk to your doctor if you experience

• mild nausea, vomiting, or decreased appetite;

• constipation, dry mouth, or blurred vision;

• hand tremor;

• muscle twitches;

• dizziness or drowsiness;

• insomnia, confusion, or nightmares;

• agitation or anxiety;

• darkening of the urine or sweat; or

• fatigue.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome. You may report side effects to FDA at 1-800-FDA-1088.

Levodopa Dosing Information

Usual Adult Dose for Parkinson's Disease:

Initial: 250 to 500 mg orally twice a day with meals.
Maintenance: 3000 to 6000 mg/day in 3 or more divided doses.

Usual Adult Dose for Restless Legs Syndrome:

50 mg orally 1 to 2 hours before bedtime (administered with a dopa-decarboxylase inhibitor)

Usual Pediatric Dose for not applicable:

Growth Hormone Deficiency Evaluation:
0.5 g/m² orally administered once.

Alternatively:
<30 lbs: 125 mg orally administered once.
30 to 70 lbs: 250 mg orally administered once.
> 70 lbs: 500 mg orally administered once.

What other drugs will affect levodopa?

Do not take levodopa if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), tranylcypromine (Parnate), or phenelzine (Nardil) within the past 2 weeks.

Antacids may increase the effectiveness of levodopa and lead to side effects. Ask your doctor about the use of antacids.

Tell your doctor if you are taking a medicine to treat high blood pressure (hypertension). Drugs taken to treat high blood pressure may be more effective when taken with levodopa, and very low blood pressure could result.

Many drugs may decrease the effects of levodopa. Tell your doctor if you are taking any of the following medicines:

• drugs used to treat seizures, such as phenytoin (Dilantin), ethotoin (Peganone), and mephenytoin (Mesantoin);

• papaverine (Pavabid, Cerespan, others);

• pyridoxine or vitamin B6;

• antidepressants such as amitriptyline (Elavil), doxepin (Sinequan), nortriptyline (Pamelor), desipramine (Norpramin), and amoxapine (Asendin); or

Levodopa may interfere with diabetic urine tests for sugar and ketones. If you are diabetic and notice changes in your urine test results, talk to your doctor before making any changes in your diabetes medication.

Drugs other than those listed here may also interact with levodopa. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

Where can I get more information?

• Your pharmacist has more information about levodopa written for health professionals that you may read.

• Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
• Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.