Treatments used for Alzheimer’s disease

As is the case for other neurodegenerative diseases, treatments fall into two categories: first, those which attempt to halt the progression of the disease and second, those which offer some alleviation of the symptoms such as anxiety, depression, psychosis and sleeplessnesss.

However, when symptoms are accompanied by a fear of taking drugs due to paranoia, or conspiratorial beliefs of being plotted against, medications may be avoided. Medication non-compliance may also arise as a result of the patient simply forgetting.

Pharmaceuticals which preserve affected cells in the brain:

The development of treatments or identifying a cure for any disease often depends on understanding the mechanisms of the condition. The discovery of reduced levels of the neurotransmitter acetylcholine (ACh) within Alzheimer’s disease combined with the knowledge that this neurotransmitter plays a pivotal role in memory, led to the development of a family of drugs which have proved beneficial in the delay of cognitive decline. The effect of these drugs focused upon inhibiting the enzyme (acetylcholinesterase) which breaks acetylcholine down.

Until more is known about the key factors which contribute to the premature death of those specific populations of brain cells involved in ‘attention’, ‘memory’ and ‘recall’, successful impediment of the progression of the disease is likely to be limited.

Drug Therapies to Date:

DRUG	DRUG TYPE	MODE of ACTION	COMMON SIDE EFFECTS
Namenda® (memantine)	N-methyl D-aspartate (NMDA) antagonist prescribed to treat symptoms of moderate to severe Alzheimer’s disease	Acts to block the toxic effects associated with excess glutamate and regulates glutamate activation	Confusion, constipation, dizziness & headache
Razadyne® (galantamine) Also available as a generic drug	Acetylcholinesterase inhibitor prescribed to treat symptoms of mild to moderate Alzheimer’s disease	Prevents the breakdown of acetylcholine and stimulates nicotinic receptors to release more acetylcholine in the brain	Diarrhoea, loss of appetite, nausea, vomiting & weight loss
Exelon® (rivastigmine)	Acetylcholinesterase inhibitor prescribed to treat symptoms of mild to moderate Alzheimer’s disease	Prevents the breakdown of acetylcholine and butyrylcholine in the brain	Diarrhoea, loss of appetite, muscle weakness, nausea, vomiting & weight loss
Aricept® (donepezil)	Cholinesterase inhibitor prescribed to treat symptoms ranging from mild to severe Alzheimer’s disease	Prevents the breakdown of acetylcholine in the brain	Diarrhoea, nausea & vomiting

Tacrine – an early acetylcholinesterase inhibitor developed by Pfizer as an oral medication prescribed to treat mild to moderate symptoms of Alzheimer’s disease. Although short-term amelioration has been reported, liver toxicity can be a serious side effect. This is rarely prescribed.