Section 04 · Monograph
Dalfampridine
Reviewed Nov 2026FDA label
AmpyraK+ channel blocker
- Forms
- ER tab: 10mg
- Dose
- 10mg BID (walking speed)
- MOA
- Improves axonal conduction in demyelinated fibers
Indications
- Improvement of walking speed in patients with multiple sclerosis (all types)FDA-labeled
Mechanism of Action
- Broad-spectrum potassium channel blocker
- Blocks voltage-gated potassium channels in demyelinated axons, prolonging action potential duration and improving conduction in demyelinated nerve fibers
Full Dosing
Adult / usual
- 10 mg orally twice daily, approximately 12 hours apart
- Do not exceed recommended dose — seizure risk is dose-dependent
- Extended-release tablet; do not crush, split, or chew
Contraindications
- History of seizures
- Moderate to severe renal impairment (CrCl ≤50 mL/min)
Drug Interactions
- Avoid other formulations of 4-aminopyridine (fampridine)
- Drugs that inhibit OCT2 transporter may increase dalfampridine exposure
Adverse Effects
- Urinary tract infection
- Insomnia
- Dizziness
- Headache
- Nausea
- Asthenia
- Back pain
- Balance disorder
- Seizures (dose-dependent risk)
Monitoring Parameters
- Renal function (CrCl) before and periodically during treatment
- Seizure history assessment before initiation
- Signs of seizure activity
Pregnancy & Lactation
- Limited human data
- Unknown if present in human milk; weigh benefits vs risks