FIRDAPSE Tablet Ref.[9961] Active ingredients: Amifampridine

2.1 Dosage Information

• The recommended starting dosage of FIRDAPSE is 15 mg to 30 mg daily, taken orally in divided doses (3 to 4 times daily).
• The dosage can be increased by 5 mg daily every 3 or 4 days.
• The maximum recommended total daily dosage is 80 mg.
• The maximum single dose is 20 mg.
• If a dose is missed, patients should not take double or extra doses.

2.2 Patients with Renal Impairment

The recommended starting dosage of FIRDAPSE in patients with renal impairment (creatinine clearance 15 to 90 mL/min) is 15 mg daily, taken orally in 3 divided doses. No dosage recommendation for FIRDAPSE can be made for patients with end-stage renal disease [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3, 12.5)].

2.3 Patients with Hepatic Impairment

The recommended starting dosage of FIRDAPSE in patients with any degree of hepatic impairment is 15 mg daily, taken orally in 3 divided doses [see Use in Specific Populations (8.7) and Clinical Pharmacology (12.3, 12.5)].

2.4 Known N-acetyltransferase 2 (NAT2) Poor Metabolizers

The recommended starting dosage of FIRDAPSE in known N-acetyltransferase 2 (NAT2) poor metabolizers is 15 mg daily, taken orally in 3 divided doses [see Use in Specific Populations (8.8) and Clinical Pharmacology (12.3, 12.5)].

2.5 Administration Instructions

FIRDAPSE can be taken without regard to food.

Overdose with FIRDAPSE was not reported during clinical studies.

In a case report, a 65-year-old patient with LEMS inadvertently received a total daily amifampridine dose of 360 mg/day (more than 4 times the maximum recommended total daily dose) and was hospitalized for general weakness, paresthesia, nausea, vomiting, and palpitations. The patient developed convulsions and paroxysmal supraventricular tachycardia, and four days after admission, experienced cardiac arrest. The patient was resuscitated and ultimately recovered following withdrawal of amifampridine.

Patients with suspected overdose with FIRDAPSE should be monitored for signs or symptoms of exaggerated FIRDAPSE adverse reactions or effects, and appropriate symptomatic treatment instituted immediately.

Store FIRDAPSE tablets at 20°C to 25°C (68°F to 77°F) with excursions permitted from 15°C to 30°C (59°F to 86°F) [see USP controlled room temperature].