Fampyra Fampridine Sustained-release Tablets

1. Indications and Usage
Multiple Sclerosis (MS):
Treatment to improve walking speed in adult patients with multiple sclerosis.
2. Dosage and Administration
Route of Administration:
For Oral Use ONLY.
Recommended Dosage:
Standard Dose: 10 mg every 12 hours (20 mg/day).
Administration: Swallow tablets whole. Do not crush, chew, or dissolve the tablets, as this destroys the sustained-release mechanism.
Frequency: Do not exceed one 10 mg tablet every 12 hours.
Critical Administration Instructions:
Empty Stomach: Should be taken on an empty stomach (do not take with food). Taking with food increases peak plasma levels and the risk of side effects.
Response Assessment: Treatment should be started on a trial basis. Efficacy is usually assessed within 2–4 weeks. If no improvement in walking speed is observed, the drug should be discontinued.
Renal Adjustment: Contraindicated in patients with moderate to severe renal impairment (Creatinine Clearance < 50 mL/min).
3. Mechanism of Action
Potassium Channel Blockade:
Fampridine is a broad-spectrum potassium (K+) channel blocker.
Restoration of Conduction:
Demyelination: In MS, the myelin sheath covering nerve fibers is damaged, causing potassium to leak out of the axons. This leak prevents electrical signals from propagating effectively.
Blocking Leak: By blocking the exposed potassium channels, Fampridine prolongs the action potential.
Therapeutic Result: This allows electrical signals to conduct more effectively past the damaged areas, thereby improving nerve conduction and clinical walking speed.
4. Safety and Warnings
Seizures (Boxed Warning):
Fampridine increases the risk of seizures.
Action: Discontinue immediately if a seizure occurs.
Renal Impairment:
The drug is primarily excreted unchanged by the kidneys. Accumulation occurs in patients with renal dysfunction, significantly increasing seizure risk.
Urinary Tract Infections:
A common side effect; monitor for symptoms like dysuria or frequency.
5.Adverse Reactions
Most Common:
Urinary tract infection, insomnia, headache, dizziness, nausea, back pain, asthenia (weakness), and balance disorder.
6.Drug Interactions
OCT2 Inhibitors (Contraindicated):
Concomitant use with drugs that inhibit Organic Cation Transporter 2 (OCT2), such as Cimetidine, is contraindicated as it significantly increases fampridine plasma concentrations.
Other Potassium Channel Blockers:
Do not use with other drugs containing 4-aminopyridine (e.g., Dalfampridine).
7.Pharmaceutical Information
Chemical Composition:
Active Ingredient: Fampridine (4-Aminopyridine).
Available Strength: 10 mg tablets.
Appearance: White to off-white, capsule-shaped tablets.
Storage: Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F).