Ampyra (dalfampridine) is an oral medication that's used to improve walking in people with multiple sclerosis (MS). It comes as a tablet that's swallowed whole twice per day. Some side effects of Ampyra (dalfampridine) include urinary tract infections, having trouble falling asleep (insomnia), and dizziness. This medication is available as a brand name and a lower-cost generic.
Improve walking in adults with multiple sclerosis (MS)
Ampyra (dalfampridine) is a potassium channel blocker. Potassium plays an important role in regulating nerve function in your body. In multiple sclerosis (MS), damaged nerves don't work well because too much potassium leaves the nerve cells through proteins called potassium channels.
It's not exactly known how Ampyra (dalfampridine) works to improve walking in people with multiple sclerosis (MS). But it's thought that Ampyra (dalfampridine) helps damaged nerves work again by blocking potassium channels on these nerve cells.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Bladder pain
bloody or cloudy urine
difficult, burning, or painful urination
frequent urge to urinate
lower back or side pain
Less common
Blurred vision
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
difficulty controlling your bladder or bowels
difficulty walking
feeling sad or depressed
forgetful
muscle cramps
problems with swallowing
slurred speech
unusual tiredness or weakness
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Confusion
epileptic seizure that will not stop
increased sweating
memory loss
reduced awareness
seizures
weakness
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Currently the only FDA-approved medication proven to improve walking in adults with MS
Can take with or without food
Available as a lower-cost generic
Can cause seizures
Not a good option for people with kidney problems because of higher risk of side effects
Might not work for everyone
Wasn't studied in children or adults ages 65 years and older
Take Ampyra (dalfampridine) twice per day about every 12 hours.
You can take Ampyra (dalfampridine) with or without food. If it's hurting your stomach, try taking it with food to help.
Swallow Ampyra (dalfampridine) tablets whole. Don't split, crush, chew, or dissolve the tablets. If you're having trouble swallowing the tablets, contact your provider.
Make sure you know how Ampyra (dalfampridine) affects you before driving or doing anything that requires your full attention. This medication can make you feel dizzy.
Let your provider know if you're taking cimetidine (Tagamet HB), an over-the-counter heartburn medication, because it interacts with Ampyra (dalfampridine). This combination of medications can raise your risk of seizures.
Ampyra (dalfampridine) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: History of seizures | Taking more than 10 mg of Ampyra (dalfampridine) twice daily
Ampyra (dalfampridine) can cause seizures, even if you've never had a seizure before. Seizures can happen within a few days to weeks after starting the medication. Let your provider know if you've had a seizure before or have a medical condition that raises your risk for seizures. Seek medical help right away if you have a seizure. You probably won't be able to continue Ampyra (dalfampridine) treatment if a seizure happens.
Risk factors: Current kidney problems
Your body gets rid of Ampyra (dalfampridine) from your system through your kidneys. If your kidneys aren't working well enough, Ampyra (dalfampridine) can build up in your system and raise your risk of side effects (e.g., seizures). It's not possible to lower the dose of Ampyra (dalfampridine) from 10 mg to lower this risk in people with kidney problems. For this reason, you shouldn't use Ampyra (dalfampridine) if you have kidney problems.
Severe allergic reactions to Ampyra (dalfampridine) are possible, including life-threatening reactions like mouth or facial swelling, shock, and anaphylaxis (closing of the throat). If you notice hives, rash, red skin, swelling of the lips or tongue, or difficulty breathing after using Ampyra (dalfampridine), stop taking the medication and get medical attention right away.
The typical dose is 10 mg by mouth twice daily (about 12 hours apart).
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
History of seizure
Moderate or severe kidney problems
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Acorda Therapeutics, Inc. (2023). Ampyra- dalfampridine tablet, film coated, extended release [package insert]. DailyMed.
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