Cholinesterase inhibitors are components of various drugs that can be used for a wide range of diseases due to their many different modes of action. Cholinesterases increase the activity of certain cell compounds, which are located in the brain as well as in various organs such as the eyes or the bladder. The available cholinesterase inhibitors differ from one another, so that the best possible active substance can be selected depending on the desired effect. However, the drugs can never be used to specifically affect just one organ, so that side effects on other organs can also result from taking them.
Indications for a cholinesterase inhibitor
Since the cell connections that mediate signals through the messenger acetylcholine can be found in very different organs of the body, there are also very different starting points and indications for cholinerase inhibitors. On the one hand, the drugs can be used to treat a mild to moderate form of Alzheimer’s dementia. In this disease, there is a deficiency of the messenger substance achetylcholine in the brain, so that by taking cholinesterase inhibitors, the breakdown of the substance is reduced, thus trying to slow down the progression of the disease.
Whether this approach actually has a positive effect is controversial, however, and the use of cholinesterase inhibitors in Alzheimer’s dementia should be weighed up individually. Completely different indications for cholinesterase inhibitors arise in the case of emptying disorders of the bladder or bowel, such as those that can occur as a result of an operation. Cholinesterase inhibitors increase the muscular activity of the bladder or intestinal wall and thus promote emptying.
Because of this effect, another important indication for cholinesterase inhibitors is the rare muscle paralysis disease myasthenia gravis. In this disease, the defective action of the immune system destroys the sites of action (receptors) of the messenger substance acetylcholine on the muscle cells, resulting in a disturbed activation of the muscle by the nervous system and thus in progressive paralysis. If left untreated, the disease can be fatal in extreme cases through paralysis of the respiratory muscles. Cholinesterase inhibitors increase the concentration of acetylcholine at the transmission point of nerves and muscles (motor end plate) so that the reduced number of receptors can be compensated and the course of the disease slowed down.
Which cholinesterase inhibitors are available on the market?
The cholinesterase inhibitors available on the pharmaceutical market can be roughly divided into two groups. – On the one hand, there are the drugs that, due to their chemical properties, can penetrate the brain and are thus used to treat dementia. These are the preparations containing the active ingredient donzepil, galantamine or rivastigmine.
The drugs are available from different manufacturers and in different dosages, although the mechanism of action does not differ. – The other large group of cholinesterase inhibitors are those which do not penetrate the brain and only reach all other body organs. The most common active ingredients on the market are neostigmine, pyridostigmine and distigmine, which are used, for example, to treat intestinal or bladder emptying disorders. This group also includes preparations with different trade names from different manufacturers.