anticholinergic

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anticholinergic

 [an″te-, an″ti-ko″lin-er´jik]
1. blocking the passage of impulses through the parasympathetic nerves.
2. an agent that has this effect; called also parasympatholytic.

an·ti·cho·lin·er·gic

(an'tē-kol-i-ner'jik),
Antagonistic to the action of parasympathetic or other cholinergic nerve fibers (for example, atropine).

anticholinergic

/an·ti·cho·lin·er·gic/ (-ko″lin-er´jik) parasympatholytic; blocking the passage of impulses through the parasympathetic nerves; also, an agent that so acts.

anticholinergic

(ăn′tē-kō′lə-nûr′jĭk, ăn′tī-)
adj.
Inhibiting or blocking the physiological action of acetylcholine at a receptor site: anticholinergic drugs.

an′ti·cho′li·ner′gic n.

anticholinergic

[-kō′lənur′jik]
Etymology: Gk, anti + chole, bile, ergein, to work
1 pertaining to a blockade of acetylcholine receptors that results in the inhibition of the transmission of parasympathetic nerve impulses.
2 an anti-cholinergic agent that functions by competing with the neurotransmitter acetylcholine for its receptor sites at synaptic junctions. Anticholinergics are used to treat spastic disorders of the GI tract, to reduce salivary and bronchial secretions before surgery, or to dilate the pupil. Some anticholinergics reduce parkinsonian symptoms but are never considered primary agents for therapy. Atropine in large doses stimulates the central nervous system and in small doses acts as a depressant. Among numerous cholinergic blocking agents are atropine, belladonna, glycopyrrolate, hyoscyamine, methixene hydrochloride, trihexyphenidyl hydrochloride, and scopolamine. Also called cholinergic-blocking agent, parasympatholytic. See also antiadrenergic.

anticholinergic

adjective Referring to an agent or effect that suppresses or inhibits acetylcholine activity.
 
noun Any agent that inhibits parasympathetic activity by blocking the neurotransmitter acetylcholine; anticholinergics are used for asthma, COPD, diarrhoea, nausea, vomiting, Parkinson’s disease and to decrease smooth muscle spasms (e.g., in the urinary bladder); anticholinergics may be antimuscarinic, ganglionic blockers and neuromuscular blockers.

anticholinergic

Parasympatholytic adjective Referring to an agent or effect that suppresses or inhibits acetylcholine activity noun Any agent that inhibits parasympathetic activity by blocking the neurotransmitter, acetylcholine; anticholinergics are used for asthma, COPD, diarrhea, N&V, Parkinson's disease, and to ↓ smooth muscle spasms–eg, in the urinary bladder; anticholinergics may be antimuscarinic, ganglionic blockers, and neuromuscular blockers

an·ti·cho·lin·er·gic

(an'tē-kō'li-nĕr'jik)
1. Antagonistic to the action of parasympathetic or other cholinergic nerve fibers (e.g., atropine).
2. Any of a class of compounds exerting anticholinergic effects. Some of these compounds (e.g., atropine) are used medicinally.

anticholinergic

Antagonistic to the action of acetyl choline or to the parasympathetic or other CHOLINERGIC nerve supply. Acetyl choline stimulates muscle contraction in the intestines and elsewhere and slows the heart. Anticholinergic substances, such as ATROPINE, relieve muscle spasm, dilate the pupils and speed up the heart.

Anticholinergic

Blocking the action of the neurohormone acetylcholine. The most obvious effects include dry mouth and dry eyes.

acetylcholine (ACh) 

A neurotransmitter substance with special excitatory properties of all preganglionic autonomic neurons, all parasympathetic postganglionic neurons and a few postganglionic sympathetic neurons. Acetylcholine is synthesized and liberated by the action of the enzyme choline acetyltranferase from the compounds choline and acetyl coenzyme A (acetyl CoA) which occurs in all cholinergic neurons. ACh exists only momentarily after its formation, being hydrolysed by the enzyme acetylcholinesterase which is present in the neurons of cholinergic nerves throughout their entire lengths and at neuromuscular junctions: this process is essential for proper muscle function as otherwise the accumulation of ACh would result in continuous stimulation of the muscles, glands and central nervous system. Alternatively a shortage of ACh has devastating effect (e.g. myasthenia gravis). ACh binds to acetylcholine receptors on skeletal muscle fibres. Sodium enters the muscle fibre membrane, which leads to a depolarization of the membrane and muscle contraction. There are two main types of acetylcholine receptors (cholinergic receptors): muscarinic receptors, which are stimulated by muscarine and ACh, belong to a family of G proteins coupled receptors and are situated in parasympathetically innervated structures (e.g. the iris and ciliary body); and nicotine receptors, which are stimulated by nicotine and ACh, are ligand-gated receptors and are situated in striated muscles (e.g. the extraocular muscles). Cholinergic receptors are found in the sympathetic and parasympathetic nervous systems, in the brain and spinal cord. The action of ACh can be either blocked or stimulated by drugs: Anticholinesterase drugs (e.g. neostigmine) inhibit acetylcholinesterase and prolong the action of acetylcholine whereas antimuscarinic drugs (also referred to as anticholinergics or parasympatholytics) such as atropine, cyclopentolate, homatropine, hyoscine and tropicamide inhibit the action of acetylcholine at muscarinic receptors. Other drugs mimic the action of ACh, they are known as parasympathomimetics (e.g. pilocarpine). See cholinergic; cycloplegia; miotics; mydriatic; neurotransmitter; nicotine; synapse; autonomic nervous system.

an·ti·cho·lin·er·gic

(an'tē-kō'li-nĕr'jik)
Antagonistic to the action of parasympathetic or other cholinergic nerve fibers (e.g., atropine).

anticholinergic (an´tīkō´linur´jik),

n (parasympatholytic, cholinolytic), a drug that acts to inhibit the effects of the neurohormone acetylcholine or to inhibit its cholinergic neuroeffects. A cholinergic blocking agent.

anticholinergic

blockade of acetylcholine receptors, resulting in the inhibition of the transmission of parasympathetic nerve impulses; parasympatholytic. Used most commonly in the nonspecific treatment of vomiting or diarrhea; includes atropine, propantheline, scopolamine, isopropamide.
References in periodicals archive ?
Anticholinergics help prevent spasms that cause asthma flare-ups, and may also help prevent the build-up of thick mucus that can accompany exacerbations.
Anticholinergics block the action of acetylcholine, a neurotransmitter that enervates the bladder, gastrointestinal tract, salivary glands, tear ducts and other bodily secretions.
To examine the association between exposure to inhaled anticholinergics and the development of acute urinary retention, Dr.
5) This may negate the benefits of AChEIs and pose risk of further harm from the anticholinergics.
However, other anticholinergic agents such as atropine have been used in the past to achieve the desired pulmonary effect.
A separate report for the Joint Expert Panel on Chronic Obstructive Pulmonary Disease of the American College of Chest Physicians and the American College of Physicians--American Society of Internal Medicine states that both are beneficial for management of acute exacerbations, but that anticholinergics should be considered first because they are associated with fewer and more benign side effects.
I never add an anticholinergic except while switching; or, at bedtime, for hypersalivation with clozapine," he said.
Medications are important to consider, especially the use of sedatives or sleepers, or overuse of antihypertensives and some medications that are strongly anticholinergic, such as some cold medications, bladder relaxants, and psychotropics.
Our study in animals suggests that anticholinergic drugs might help to alleviate these symptoms, and this is supported by the recent clinical data.
In addition, "regulators ought to review safety data for all inhaled bronchodilators, with particular attention to vulnerable subgroups at the highest risk of systemic anticholinergic effects, such as older men with BPH or patients with preexisting arrhythmias, who are often excluded from randomized controlled trials of efficacy," they said.
2] When behavioural strategies fail to achieve adequate control of OAB symptoms, anticholinergic medications are advocated next.
The prescription and over-the-counter drugs, known as anticholinergic medications, have long been thought to have negative effects on brain functioning, and a recent study suggests that using them on a long-term basis can cause impairment in memory and cognition in older people.