What Are Cholinergic Drugs?

Identification

• Cholinergic drugs are prescription medications designed to mimic the actions of acetylcholine. Acetylcholine is a neurotransmitter responsible for maintaining the body's parasympathetic nervous system. The parasympathetic nervous system regulates body processes like digestion, blood pressure, breathing and heart rate. Acetylcholine is also an essential chemical used within the brain for memory processes. When the body is lacking in acetylcholine, cholinergic drugs may be prescribed to help regulate body processes. These drugs come in capsules, tablets, injection-form and eye drops.
  
  

Acetylcholine Functions

• The nerve cells of the somatic and sympathetic nervous systems secrete acetylcholine. The somatic system is made up of all the muscles in the body. Acetylcholine's main job is to promote movement of the muscles involved in these systems. When secreted, it produces signal transmissions that move from one nerve to the next. Each nerve affected also secretes acetylcholine. Once the signal transmission has run its course, acetylcholine is broken down into its component parts--choline and acetate--to be recycled for reuse. Cholinergic drugs are used to mimic this process.
  
  

Drug Effects

• Cholinergic drugs can affect the nervous system in two different ways. Some are designed to increase acetylcholine secretions in the body, while others work to allow acetylcholine to remain in the system longer. Also called acetylcholine inhibitors, these drugs work by allowing acetylcholine secretions to remain in the system for a longer period. They do this by blocking the release of acetylcholinesterase, which is an enzyme secreted by nerve cells. This enzyme works to eliminate acetylcholine. By blocking this enzyme, acetylcholine is able to remain active in the system.
  
  

Drug Uses

• Cholinergic drugs can be used to treat a number of conditions. A form of these drugs can treat any condition where muscle weakness is a factor. Myasthenia gravis is one such condition where muscles become progressively weakened. Drugs used in the treatment of myasthenia gravis include Mestinon, Prostigmine and Tensilon. Patients who have undergone surgery may also suffer from muscle weakness as result of anesthetic drugs that were administered. Under these circumstances, the same set of drugs used to treat myasthenia gravis can be used as well. Glaucoma is another condition where cholinergic drugs are used to help reduce the pressure inside the eye. Humorsol and Phospholine Iodide are a few of the drugs used to treat glaucoma patients.
  
  

Warnings

• Because of the effects of cholinergic drugs on the parasympathetic nervous system, patients with certain conditions may suffer adverse reactions when treated with these drugs. Any digestive problems or slowed heart rhythms may become worse if acetylcholine levels are altered. Persons with asthma and epilepsy are also at risk of experiencing adverse effects. As with most any prescription drug, side effects are possible. Potential side effects caused by cholinergic drugs include breathing problems, nausea, headaches, muscle pain and drowsiness.