Generic name: foscarbidopa and foslevodopa
Brand name: Vyalev
Dosage form: subcutaneous solution (12 mg-240 mg/mL)
Drug class: Dopaminergic antiparkinsonism agents

Medically reviewed by Drugs.com on Jan 17, 2025. Written by Cerner Multum.

What is foscarbidopa and foslevodopa?

Foscarbidopa and foslevodopa is a combination medicine used in adults to treat advanced Parkinson's disease.

Foscarbidopa and foslevodopa may also be used for purposes not listed in this medication guide.

Foscarbidopa and foslevodopa side effects

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

Tell your doctor right away if you have new or sudden changes in mood or behavior, including depression or anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, aggressive, more active or talkative, or have thoughts about suicide or hurting yourself.

Some side effects may occur during the injection. Tell your medical caregiver if you feel dizzy, nauseated, light-headed, itchy, sweaty, or have a headache, chest tightness, back pain, trouble breathing, or swelling in your face.

Foscarbidopa and foslevodopa may cause serious side effects. Call your doctor at once if you have:

• fever, very stiff (rigid) muscles, high fever, sweating, confusion;

• hallucinations (seeing or hearing things that are not real);

• bruising, swelling, warmth, redness, oozing, or bleeding where an injection was given;

• uncontrolled muscle movements, blurred vision, eye pain or redness, seeing halos around lights; or

• high blood pressure, fast or pounding heartbeats, or chest pain.

You may have increased sexual urges, unusual urges to gamble, or other intense urges while taking foscarbidopa and foslevodopa. Talk with your doctor if this occurs.

Your dose may be reduced or permanently discontinued if you have certain side effects.

Common side effects of foscarbidopa and foslevodopa may include:

• infection where an injection was given;

• drowsiness;

• uncontrolled muscle movements; or

• hallucinations.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

Do not use this medicine if you have used a MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, or tranylcypromine.

Before taking this medicine

You should not use foscarbidopa and foslevodopa if you are allergic to it.

Do not use foscarbidopa and foslevodopa if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, and tranylcypromine. Wait at least 14 days after stopping an MAO inhibitor before you take foscarbidopa and foslevodopa.

Tell your doctor if you have or have ever had:

• sleepiness or problems falling asleep suddenly during the day;

• heart disease, abnormal heart rate, high blood pressure, or heart attack;

• problems with muscle movement;

• unusual changes in mood or behavior, hallucinations;

• increased sexual urges, unusual urges to gamble, or other intense urges;

• glaucoma; or

• if you drink alcohol.

It is not known if foscarbidopa and foslevodopa will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using foscarbidopa and foslevodopa.

How should I use foscarbidopa and foslevodopa?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Foscarbidopa and foslevodopa is injected under the skin using an infusion pump over a 24-hour period.

A healthcare provider will program the pump and show you how to use it. Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you do not understand these instructions.

A healthcare provider will show you where to inject foscarbidopa and foslevodopa. Do not inject into the same place two times in a row. Remember to change the skin site where the infusion is injected at least every 3 days.

Do not inject within 2 inches of your navel (belly button), or areas where the skin is tender, bruised, red, or has scars.

You may be given instructions to take oral carbidopa and levodopa if you stop the infusion for longer than 1 hour.

You may stop this medicine for a short amount of time to do things like take a shower or medical procedure. You may need to give loading dose if you stop the infusion for longer than 3 hours. Follow your doctor's instructions very carefully.

Call your doctor if your symptoms do not improve, or if they get worse.

Do not stop using foscarbidopa and foslevodopa suddenly, or you could have unpleasant symptoms (such as fever, confusion, or muscle stiffness). Ask your doctor before stopping the medicine.

You may need frequent vision exams.

Each vial (bottle) is for one use only. Throw away after one use, even if there is still medicine left inside. Place them in a puncture-proof "sharps" container and dispose of it following state or local laws. Keep out of the reach of children and pets.

Store this medicine in the original container in the refrigerator, do not freeze or shake the medicine.

You may store this medicine at room temperature for up to 28 days. Throw the medicine away if not used within 28 days. Do not put it back into the refrigerator.

Foscarbidopa and foslevodopa dosing information

Usual Adult Dose for Parkinson's Disease:

Initial dose: Individualized based on the total levodopa dosage (TLD) the patient was previously receiving.
Maximum dose (foslevodopa): 3525 mg/day (equivalent to about 2500 mg of levodopa per day), via subcutaneous infusion

Comments:
-Consult the manufacturer product information for instructions on calculations and determination of infusion rates and dosing volumes.
-The continuous infusion rate is based on TLD.
-Adjust infusion rates in increments of 0.01 mL/hr (about 1.7 mg levodopa/hr).

Use: For the treatment of motor fluctuations in adults with advanced Parkinson's disease (PD)

What happens if I miss a dose?

Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using foscarbidopa and foslevodopa?

Avoid driving or hazardous activity until you know how foscarbidopa and foslevodopa will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries. Also avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

Drinking alcohol with this medicine can cause side effects.

What other drugs will affect foscarbidopa and foslevodopa?

Using foscarbidopa and foslevodopa with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

When you start or stop taking foscarbidopa and foslevodopa, your doctor may need to adjust the doses of other medicines you use on a regular basis.

Tell your doctor about all your other medicines, especially:

• isoniazid; or

• medicine to treat blood pressure, nausea or vomiting, anxiety, mood disorders, or mental illness such as schizophrenia.

This list is not complete. Other drugs may affect foscarbidopa and foslevodopa, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

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.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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