Dalfampridine
AMPYRA
What it isPotassium channel blocker improving conduction in demyelinated axons; walking in multiple sclerosis.
Why this oneIt improves walking speed regardless of MS subtype, which no disease-modifying therapy does directly.
What limits itSeizures, dose-related and the reason the dose must never be exceeded. Renally cleared; contraindicated below eGFR 50.
FDA-approved for
- MS walking (2010)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Improve walking in multiple sclerosis | Adults | 10 mg BID (~12 h apart) | 10 mg BID | 10 mg BID |
Renal Contraindicated in moderate–severe renal impairment (CrCl ≤50 mL/min); use caution in mild impairment (CrCl 51–80) — increased seizure risk
Hepatic Undefined
Do not exceed 10 mg BID — no added benefit and higher seizure risk above this dose
Instructions
- Swallow tablet whole; do not divide, crush, chew, or dissolve
- Take with or without food
- If a dose is missed, do not take a double or extra dose
- Permanently discontinue if a seizure occurs
Contraindications
- History of seizure
- Moderate or severe renal impairment (CrCl ≤50 mL/min)
Cautions
- Dose-dependent seizure risk
- Avoid concomitant use with other 4-aminopyridine (4-AP, fampridine) products
- Anaphylaxis
Adverse reactions
- Urinary tract infection
- Insomnia
- Dizziness
- Headache
- Nausea
- Asthenia
- Back pain
- Balance disorder
- Paresthesia
Pregnancy No adequate human data; animal data show decreased offspring viability and growth
Lactation Undefined
NO BOXED WARNINGS
Principal riskSeizures; never exceed the dose, avoid below eGFR 50
Cost, est. cash$10–$500/month
Generic entry2017
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
Mechanism of action: Dalfampridine ballicule
