From the Guidelines
The most effective treatment for neurocognitive diseases, such as Alzheimer's disease and vascular dementia, involves the use of cholinesterase inhibitors, including donepezil, rivastigmine, and galantamine, which have been shown to improve cognitive function and slow disease progression, as supported by the most recent and highest quality study 1. For mild to moderate Alzheimer's disease, these medications are first-line treatments that work by increasing acetylcholine levels in the brain to improve cognitive function. Some key points to consider when treating neurocognitive diseases include:
- The use of cholinesterase inhibitors, such as donepezil, rivastigmine, and galantamine, which have been shown to improve cognitive function and slow disease progression 1.
- The potential benefits and risks of memantine, which regulates glutamate activity and may be used in combination with cholinesterase inhibitors 1.
- The importance of individualizing treatment based on disease stage, comorbidities, and potential side effects, as well as considering the patient's preferences and prior expressed wishes 1.
- The need to gradually deprescribe cholinesterase inhibitors and memantine, with dose reduction by 50% every 4 weeks, to minimize potential withdrawal effects 1. Some medications that may be used to treat neurocognitive diseases include:
- Donepezil (Aricept, 5-10mg daily)
- Rivastigmine (Exelon, 1.5-6mg twice daily or 4.6-13.3mg/24hr patch)
- Galantamine (Razadyne, 8-24mg daily)
- Memantine (Namenda, 5-20mg daily) It is essential to note that these medications primarily manage symptoms rather than cure the underlying conditions, and treatment should be tailored to the individual patient's needs and circumstances, as supported by the evidence from 1, which is the most recent and highest quality study.
From the FDA Drug Label
Memantine hydrochloride is indicated for the treatment of moderate to severe dementia of the Alzheimer’s type. Memantine hydrochloride was evaluated in eight double-blind placebo-controlled trials involving a total of 1862 dementia (Alzheimers disease, vascular dementia) patients
The available drug for treating neurocognitive diseases, such as Alzheimer's disease and vascular dementia, is memantine.
- Key Indications:
- Moderate to severe dementia of the Alzheimer’s type
- Vascular dementia
- Dosage: The recommended starting dose of memantine hydrochloride is 5 mg once daily, with a target dose of 20 mg/day (5 mL twice daily) 2. The dosage may need to be adjusted in patients with severe renal impairment or hepatic impairment.
- Administration: Memantine hydrochloride can be taken with or without food, and should be administered with a dosing device that comes with the drug 2.
From the Research
Available Drugs for Neurocognitive Diseases
The following drugs are available for treating neurocognitive diseases, such as Alzheimer's disease and vascular dementia:
- Cholinesterase inhibitors: donepezil, galantamine, and rivastigmine 3, 4, 5, 6, 7
- N-methyl-D-aspartate receptor antagonist: memantine 3, 5, 6, 7
Efficacy of Available Drugs
The efficacy of these drugs in improving cognitive function and other symptoms of neurocognitive diseases is as follows:
- Donepezil: improves cognition, global function, and activities of daily living in patients with vascular dementia 3 and Alzheimer's disease 6
- Galantamine: improves cognition in patients with vascular dementia and Alzheimer's disease 4, 7
- Rivastigmine: may provide some cognitive benefit in vascular dementia, but the evidence is less certain 4
- Memantine: may provide some cognitive benefit in vascular dementia and Alzheimer's disease, but the evidence is limited 3, 6, 7
Adverse Events
The adverse events associated with these drugs are:
- Donepezil: nausea, vomiting, diarrhea, dizziness, headache, and hypertension 4
- Galantamine: nausea, vomiting, diarrhea, dizziness, headache, and hypertension 4
- Rivastigmine: nausea, vomiting, diarrhea, dizziness, headache, and hypertension 4
- Memantine: generally well-tolerated, but may cause dizziness, headache, and confusion 6, 7
Comparison of Available Drugs
A network meta-analysis comparing the efficacy and safety of these drugs found that:
- Donepezil 10 mg had the greatest effect on cognition, but was also associated with more adverse events 4
- Galantamine 16-24 mg had a moderate effect on cognition and was associated with some adverse events 4
- Rivastigmine had a smaller effect on cognition and was associated with uncertain adverse events 4
- Memantine had a limited effect on cognition and was generally well-tolerated 6, 7