"March 7, 2012 -- The Alzheimer's drug Aricept helps people with early to moderate signs of the disease maintain a higher level of function, but just how long the drug continues working is not fully understood. A new study may help clear up some c"...
Patient Counseling Information
See FDA-approved patient labeling (PATIENT INFORMATION and Instructions for Use).
To assure safe and effective use of NAMENDA, the following information and instructions provided in the patient information section should be discussed with patients and caregivers.
Patients/caregivers should be instructed to follow the dose titration schedule provided by their physician or healthcare professional for NAMENDA.
If a patient misses a single dose of NAMENDA, that patient should not double up on the next dose. The next dose should be taken as scheduled. If a patient fails to take NAMENDA for several days, dosing should not be resumed without consulting that patient's healthcare professional.
Patients/caregivers should be instructed on how to use the NAMENDA oral solution dosing device. They should be made aware of the patient instruction sheet that is enclosed with the product. Patients/caregivers should be instructed to address any questions on the usage of the solution to their physician or pharmacist.
Carcinogenesis, Mutagenesis, Impairment Of Fertility
There was no evidence of carcinogenicity in a 113-week oral study in mice at doses up to 40 mg/kg/day (10 times the maximum recommended human dose [MRHD] on a mg/m² basis). There was also no evidence of carcinogenicity in rats orally dosed at up to 40 mg/kg/day for 71 weeks followed by 20 mg/kg/day (20 and 10 times the MRHD on a mg/m² basis, respectively) through 128 weeks.
Memantine produced no evidence of genotoxic potential when evaluated in the in vitro S. typhimurium or E. coli reverse mutation assay, an in vitro chromosomal aberration test in human lymphocytes, an in vivo cytogenetics assay for chromosome damage in rats, and the in vivo mouse micronucleus assay. The results were equivocal in an in vitro gene mutation assay using Chinese hamster V79 cells.
No impairment of fertility or reproductive performance was seen in rats administered up to 18 mg/kg/day (9 times the MRHD on a mg/m² basis) orally from 14 days prior to mating through gestation and lactation in females, or for 60 days prior to mating in males.
Use In Specific Populations
Pregnancy Category B
There are no adequate and well-controlled studies of memantine in pregnant women. NAMENDA should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Memantine given orally to pregnant rats and pregnant rabbits during the period of organogenesis was not teratogenic up to the highest doses tested (18 mg/kg/day in rats and 30 mg/kg/day in rabbits, which are 9 and 30 times, respectively, the maximum recommended human dose [MRHD] on a mg/m² basis).
Slight maternal toxicity, decreased pup weights and an increased incidence of non-ossified cervical vertebrae were seen at an oral dose of 18 mg/kg/day in a study in which rats were given oral memantine beginning pre-mating and continuing through the postpartum period. Slight maternal toxicity and decreased pup weights were also seen at this dose in a study in which rats were treated from day 15 of gestation through the postpartum period. The no-effect dose for these effects was 6 mg/kg, which is 3 times the MRHD on a mg/m² basis.
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when NAMENDA is administered to a nursing mother.
Safety and effectiveness in pediatric patients have not been established.
The majority of people with Alzheimer's disease are 65 years and older. In the clinical studies of NAMENDA the mean age of patients was approximately 76; over 90% of patients were 65 years and older, 60% were 75 years and older, and 12% were at or above 85 years of age. The efficacy and safety data presented in the clinical trial sections were obtained from these patients. There were no clinically meaningful differences in most adverse events reported by patient groups ≥ 65 years old and < 65 year old.
No dosage adjustment is needed in patients with mild or moderate renal impairment. A dosage reduction is recommended in patients with severe renal impairment [see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY].
No dosage adjustment is needed in patients with mild or moderate hepatic impairment. NAMENDA should be administered with caution to patients with severe hepatic impairment [see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY].
Last reviewed on RxList: 9/25/2014
This monograph has been modified to include the generic and brand name in many instances.
Additional Namenda Information
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