2.1 Galantamine Hydrobromide Tablets, USP
The dosage of galantamine hydrobromide tablets shown to be effective in controlled clinical trials is 16-32 mg/day given as twice daily dosing. As the dosage of 32 mg/day is less well tolerated than lower dosages and does not provide increased effectiveness, the recommended dosage range is 16-24 mg/day given twice daily. The dosage of 24 mg/day did not provide a statistically significant greater clinical benefit than 16 mg/day. It is possible, however, that a daily dosage of 24 mg of galantamine might provide additional benefit for some patients.
The recommended starting dosage of galantamine hydrobromide tablets is 4 mg twice a day (8 mg/day). The dosage should be increased to the initial maintenance dosage of 8 mg twice a day (16 mg/day) after a minimum of 4 weeks. A further increase to 12 mg twice a day (24 mg/day) should be attempted after a minimum of 4 weeks at 8 mg twice a day (16 mg/day).
Dosage increases should be based upon assessment of clinical benefit and tolerability of the previous dose.
Galantamine hydrobromide tablets should be administered twice a day, preferably with morning and evening meals.
Patients and caregivers should be advised to ensure adequate fluid intake during treatment.
If therapy has been interrupted for more than three days, the patient should be restarted at the lowest dosage and the dosage escalated to the current dose.
The abrupt withdrawal of galantamine hydrobromide tablets in those patients who had been receiving dosages in the effective range was not associated with an increased frequency of adverse events in comparison with those continuing to receive the same dosages of that drug. The beneficial effects of galantamine hydrobromide tablets are lost, however, when the drug is discontinued.
2.2 Dosage in Patients with Hepatic Impairment
In patients with moderate hepatic impairment (Child-Pugh score of 7-9), the dosage should generally not exceed 16 mg/day. The use of galantamine hydrobromide tablets in patients with severe hepatic impairment (Child-Pugh score of 10-15) is not recommended [see Clinical Pharmacology (12.3)].
2.3 Dosage in Patients with Renal Impairment
In patients with creatinine clearance of 9 to 59 mL/min, the dosage should generally not exceed 16 mg/day. In patients with creatinine clearance less than 9 mL/min, the use of galantamine hydrobromide tablets is not recommended [see Clinical Pharmacology (12.3)].