Multiple sclerosis: Oral: 10 mg every 12 hours (maximum daily dose: 20 mg); no additional benefit seen with doses >20 mg daily
Missed doses: Do not administer double or extra doses if a dose is missed.
Note: CrCl is estimated with Cockcroft-Gault formula.
Mild renal impairment (CrCl 51 to 80 mL/minute): There are no dosage adjustments recommended by the manufacturer; however, use with extreme caution as risk of seizure may be increased secondary to reduced clearance.
Moderate to severe renal impairment (CrCl ≤50 mL/minute): Use is contraindicated.
No dosage adjustment required; drug undergoes minimal metabolism and is primarily excreted unchanged in the urine.
Refer to adult dosing.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet Extended Release 12 Hour, Oral:
Ampyra: 10 mg
Generic: 10 mg
Yes
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet Extended Release 12 Hour, Oral:
Fampyra: 10 mg
Generic: 10 mg
An FDA-approved patient medication guide, which is available with the product information and at https://www.accessdata.fda.gov/drugsatfda_docs/label/2021/022250s018lbl.pdf#page=13, must be dispensed with this medication.
Oral:
May be administered with or without food. Do not chew, crush, dissolve, or divide tablet.
Bariatric surgery: Tablet, extended release: Some institutions may have specific protocols that conflict with these recommendations; refer to institutional protocols as appropriate. Film-coated tablet; do not cut, crush or chew. No IR formulation available.
Multiple sclerosis: Treatment to improve walking in patients with multiple sclerosis.
Ampyra may be confused with anakinra
Dalfampridine may be confused with delavirdine, desipramine
Dalfampridine (US) and fampridine (Canada) are different generic names for the same chemical entity (4-aminopyridine)
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
>10%: Genitourinary: Urinary tract infection (12%)
1% to 10%:
Gastrointestinal: Constipation (3%), dyspepsia (2%), nausea (7%)
Nervous system: Balance impairment (5%), dizziness (7%), headache (7%), insomnia (9%), paresthesia (4%)
Neuromuscular & skeletal: Acute exacerbations of multiple sclerosis (4%), asthenia (7%), back pain (5%)
Respiratory: Nasopharyngitis (4%), pharyngolaryngeal pain (2%)
Frequency not defined:
Hypersensitivity: Anaphylaxis, angioedema, severe hypersensitivity reaction
Nervous system: Confusion, seizure
Postmarketing:
Gastrointestinal: Vomiting
Nervous system: Vertigo
Hypersensitivity to dalfampridine, 4-aminopyridine, or any component of the formulation; history of seizure; moderate or severe renal impairment (CrCl ≤50 mL/minute).
Canadian labeling: Additional contraindications (not in US labeling): Concomitant use with compounded 4-aminopyridine or other forms of fampridine; concomitant use with drugs that inhibit organic cation transporter 2 (OCT2), such as cimetidine or quinidine.
Concerns related to adverse reactions:
• Anaphylaxis: May cause anaphylaxis or severe allergic reactions; symptoms have included respiratory compromise, urticaria, and angioedema (throat and tongue). Discontinue immediately and administer appropriate medical care if a severe allergic reaction occurs.
• Seizures: Associated with a dose-dependent risk of seizure; seizures may occur within days to weeks after treatment initiation and have been reported more frequently in patients with no history of seizures. Discontinue use and do not reinitiate therapy if seizure occurs during treatment. Assess risk of seizure prior to treatment initiation; use caution or avoid in patients who may have a lower seizure threshold due to predisposing factors.
• Urinary tract infection: Urinary tract infections were reported more frequently in patients receiving dalfampridine (compared to placebo),
Disease-related concerns:
• Renal impairment: Use in renal impairment is associated with an increased risk of seizure and other adverse events, primarily neurologic effects, due to increased serum concentrations; elimination is predominately via the kidneys as unchanged drug.
Concurrent drug therapy issues:
• 4-aminopyridine formulations: Sustained release products available in the United States (dalfampridine) or in Canada (fampridine) should not be administered with other 4-aminopyridine formulations (eg, compounded immediate release fampridine).
Other warnings/precautions:
• Name confusion: The chemical entity of 4-aminopyridine is referred to with a generic name of dalfampridine in the US and with a generic name of fampridine in Canada.
Substrate of CYP2E1 (minor); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential
Cimetidine: May increase the serum concentration of Dalfampridine. Management: The potential benefits of taking cimetidine concurrently with dalfampridine should be considered against the risk of seizures in these patients. Some non-US labeling contraindicates the use of dalfampridine with cimetidine. Risk D: Consider therapy modification
Dolutegravir: May increase the serum concentration of Dalfampridine. Management: Consider alternatives to this combination. Carefully weigh the risk of seizures against the benefit of combining dolutegravir with dalfampridine. Non-US labels list this combination as contraindicated. Risk D: Consider therapy modification
MetFORMIN: May increase the serum concentration of Dalfampridine. Dalfampridine may increase the serum concentration of MetFORMIN. Risk C: Monitor therapy
QuiNIDine: May increase the serum concentration of Dalfampridine. Management: The potential benefits of taking quinidine concurrently with dalfampridine should be considered against the risk of seizures in these patients. Some non-US labeling contraindicates the use of dalfampridine with quinidine. Risk D: Consider therapy modification
Trilaciclib: May increase the serum concentration of Dalfampridine. Management: Consider alternatives to this combination. Carefully weigh the risk of seizures against the benefit of combining trilaciclib with dalfampridine. Risk D: Consider therapy modification
Information related to the use of dalfampridine in pregnancy is limited (Maillart 2016).
It is not known if dalfampridine is present in breast milk.
According to the manufacturer, the decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and benefits of treatment to the mother. Based on its chemical properties, others recommend breastfeeding be avoided until additional information is available (Almas 2016).
May be taken with or without food.
Renal function (baseline and at least annually thereafter); EEG; walking ability
Nonspecific potassium channel blocker which improves conduction in focally demyelinated axons by delaying repolarization and prolonging the duration of action potentials. Enhanced neuronal conduction is thought to strengthen skeletal muscle fiber twitch activity, thereby, improving peripheral motor neurologic function.
Absorption: Rapid and complete
Distribution: Vd: 2.6 L/kg
Protein binding: Negligible; predominantly unbound to plasma proteins
Metabolism: Limited metabolism; in vitro data suggests hepatic metabolism to 3-hydroxy-4-aminopyridine occurs primarily via CYP2E1; further conjugated to 3-hydroxy-4-aminopyridine sulfate; metabolites are inactive
Bioavailability: 96% (relative to aqueous solution)
Half-life elimination: 5.2-6.5 hours; prolonged in severe renal impairment (~3 times longer)
Time to peak, plasma: 3-4 hours
Excretion: Urine (96%; 90% of total dose as unchanged drug); feces (0.5%)
Renal function impairment: Total body clearance of dalfampridine is reduced by ~45% in patients with mild renal impairment (CrCl 51-80 mL/minute), by ~50% in patients with moderate renal impairment (CrCl 30-50 mL/minute), and by ~75% in patients with severe renal impairment (CrCl <30 mL/minute).
Geriatric: Clearance modestly decreased with increasing age, but not significantly enough to necessitate a dose modification.
Gender: A pharmacokinetic analysis suggested that women would be expected to have slightly higher Cmax than men.
Tablet, 12-hour (Ampyra Oral)
10 mg (per each): $70.36
Tablet, 12-hour (Dalfampridine ER Oral)
10 mg (per each): $47.37 - $48.45
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.