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Amifampridine Phosphate

What is Firdapse used for?

Amifampridine phosphate is used to treat a certain disorder that affects nerves and muscles (Lambert-Eaton syndrome). This disorder causes your body's immune system to attack healthy nerve cells, which results in muscle weakness. It is not known exactly how this medication works, but it can help lessen symptoms of muscle weakness and loss of movement caused by Lambert-Eaton syndrome.


Amifampridine Phosphate


Muscular Dystrophies
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What does Firdapse look like?

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Firdapse Frequently Asked Questions

Read the Medication Guide provided by your pharmacist before you start taking amifampridine phosphate and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually 3 to 4 times daily. The dosage is based on your medical condition and response to treatment. Children's dose is also based on weight. To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose and gradually increase your dose. Follow your doctor's instructions carefully.

If you need a dose that doesn't match taking half and/or whole tablets together, or have trouble swallowing tablets, or receive medication through a feeding tube, you may make a liquid suspension with this medication. Read and follow the manufacturer's directions (Instructions for Use leaflet) to make a suspension with the tablet(s) and sterile water. Ask your doctor or pharmacist about what you need to make the suspension. Place the required number of tablets in a container. Add 10 milliliters (2 teaspoonfuls) sterile water to the container for each tablet. Do not use any other foods or liquids to mix this medication. Wait 5 minutes, then shake the mixture well for 30 seconds. Shake the suspension well before measuring each dose. Carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose. Refrigerate the suspension between doses. Prepare fresh suspensions daily. Throw away any unused suspension after 24 hours.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day.

Tell your doctor if your condition does not get better or if it gets worse.

IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Firdapse Dosage and Form Information

10 Mg