Cholinesterase inhibitors for dementia
Blocking acetylcholinesterase so more acetylcholine stays in the brain.
Also called acetylcholinesterase inhibitors and AChE inhibitors.
Class card
- Drugs
- Donepezil and Rivastigmine
- Used for
- Dementia of Alzheimer's disease
- Dementia in Parkinson's disease
- Known for
- Nausea, vomiting and diarrhea
- Slow heart rate, heart block or fainting
- Name stems
- -stigmine
- Part of
- anticholinesterases
3 cards: the class, and each drug in it.
Mechanism of action
How do cholinesterase inhibitors for dementia work?
These drugs enter the brain and inhibit acetylcholinesterase, the enzyme that breaks down acetylcholine, so more acetylcholine stays at the synapses of the cholinergic neurons that still work in Alzheimer's or Parkinson's dementia. Memory and thinking improve for a time, but the disease is not slowed and the benefit fades as neurons are lost. Extra acetylcholine in the gut and heart causes the main side effects.
The drugs
Cholinesterase inhibitors for dementia with a card
- DonepezilIt inhibits acetylcholinesterase only, unlike rivastigmine, and is the one licensed in the US for severe as well as mild to moderate Alzheimer's disease.
- RivastigmineUnlike donepezil it also blocks butyrylcholinesterase, is broken down by cholinesterases rather than the liver's CYP enzymes, and comes as a skin patch.
Uses
What are cholinesterase inhibitors for dementia used for?
- Dementia of Alzheimer's disease
- Dementia in Parkinson's disease
Side effects
Side effects of cholinesterase inhibitors for dementia
- Nausea, vomiting and diarrheaKnown for
- Slow heart rate, heart block or faintingKnown forSerious
- Loss of appetite and weight loss
- Stomach ulcers and bleedingSerious
- SeizuresSerious
- Difficulty passing urine
- Insomnia and abnormal dreams
- Muscle cramps
- Worse tremor in Parkinson's disease
What the class has in common. Each drug's card has its own, and Known for marks what an exam expects you to know.
Watch for
Cautions
- They exaggerate the muscle relaxation of suxamethonium during anesthesia.
- Beta blockers and other heart-slowing drugs add to the bradycardia; care in conduction disease.
- Anticholinergic drugs such as oxybutynin oppose their effect.
- A history of peptic ulcer, NSAID use, asthma or COPD calls for care.
Remember them
A way to remember them
More acetylcholine: a slower heart and a busier gut.
Outside the brain the extra acetylcholine slows the heart (bradycardia, heart block, fainting) and stirs the gut (nausea, vomiting, diarrhea), the two side effects these drugs are known for.
Written for biofideX
Name stems
-stigmine means cholinesterase inhibitor
Neostigmine reverses non-depolarizing muscle relaxants and rivastigmine treats dementia. Donepezil, a cholinesterase inhibitor used for dementia, doesn't carry the stem.
- Every drug name stem
Don't mix them up
Classes easily confused with these
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- Donepezil hydrochloride tablets: label (DailyMed)
- Rivastigmine tartrate capsules: label (DailyMed)
- Rivastigmine: product information (EMA)
- Donepezil (NHS)
For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.
Parkinson's, dementia and migraine
Practice cholinesterase inhibitors for dementia with the other classes in this group: what each drug is, how it works, what it treats and what it's known for.
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