Atropine side effects

Selective muscarinic receptor blocker. It inhibits gastric secretion. Thus is effective in peptic ulcer patients and promotes ulcer healing. It does not produce atropinic side effect (due to blockade of and M3 receptors). 

Although structures with anticholinergic (atropine-like) activities continue to be synthesized and studied, non-anticholinergic spasmolytics also have considerable clinical potential. Mebeverine, a compound of this type, was marketed abroad several years ago it has recently been reported to act by blocking uptake of norepinephrine as well as by a nonspecific depressant effect.Two new series of compounds were synthesized by removal of the alcoholic OH group from the -carbon atom of certain atropine derivatives these compounds retained spasmolytic action, but lacked atropinic "side effects".120 pharmacology of one of these... 

These include atropine, scopolamine (hyoscine), trihexyphenidyl (benzhexol) and benzatropine. They block central muscarinic receptors involved in various afferent pathways of the vomiting reflex (Fig. 1). They have been used to control motion sickness, emesis in Meniere s disease and postoperative vomiting. Currently, hyoscine is largely restricted to the treatment of motion sickness where it has a fast onset of action but a short duration (4-6 h). Administration of hyoscine by transdermal patch produces a prolonged, low-level release of the drug with minimal side effects. To control postoperative vomiting, it should be applied >8 h before emesis is anticipated. 

Inspection of the retina during an ophthalmoscopic examination is greatly facilitated by mydriasis, or the dilation of the pupil. Parasympathetic stimulation of the circular muscle layer in the iris causes contraction and a decrease in the diameter of the pupil. Administration of a muscarinic receptor antagonist such as atropine or scopolamine prevents this smooth muscle contraction. As a result, sympathetic stimulation of the radial muscle layer is unopposed, causing an increase in the diameter of the pupil. These agents are given in the form of eye drops that act locally and limit the possibility of systemic side effects. 

Anticholinergic drugs, such as atropine, block vagal tone and prolong gut transit time. Their value in controlling diarrhea is questionable and limited by side effects. 

Nerve Agent Antidote Kit (NAAK or MARK I) consists of an atropine auto-injector (2 mg), a pralidoxime chloride auto-injector (2-Pam-Cl, 600 mg), the plastic clip joining the two injectors, and a foam case. The kit serve as a countermeasure to nerve agents, including tabun (GA), sarin (GB), soman (GD), GF, and VX. Military personnel can receive three MARK I for self/buddy aid. Possible side effects of atropine and/or 2-PAM-C1 are deemed insignificant in a nerve agent casualty. Intravenous atropine and 2-PAM-C1 can also be made available. The MARK I kit is manufactured by Survival Technology, Inc., Rockville, Maryland. 

Compared with neostigmine,2 D.F.P. produced side effects more commonly and these arose in spite of administration of atropine (0-01 gr.) in an attempt to control the gut symptoms. There were no changes in liver, kidney or haemopoietic function ascribed to D.F.P. Asthma was considered a contra-indication to the use of D.F.P. It can thus be seen that D.F.P. in therapeutic dosage is a safe medicament.3... 

Quaternary ammonium compounds are less lipid-soluble and therefore tend to cause fewer central atropine-like side-effects, whereas peripheral side-effects... 

Another recent review [198] of published material pointed out that the animal work on atropine-like side effects had still not been published in full and, in any case, required independent corroboration. None the less, it was agreed that the clinical evidence (in spite of the difficulties of evaluation) did point to... 

Central Motor restlessness, progressing to maniacal agitation, psychic disturbances, disorientation, and hallucinations. Elderly subjects are more sensitive to such central effects, in this context, the diversity of drugs producing atropine-like side effects should be borne in mind e.g., tricyclic antidepressants, neuroleptics, antihistamines, antiarrhythmics, antiparkinsonian agents. 

The cholinoceptor antagonist pi-renzepine, unlike atropine, prefers cho-linoceptors of the Mi type, does not penetrate into the OIS, and thus produces fewer atropine-like side effects (p. 104). The cholinoceptors on parietal cells probably belong to the M3 subtype. Hence, pirenzepine may act by blocking Ml receptors on ECL cells or submucosal neurons. 

The side effects of tricyclic antidepressants are largely attributable to the ability of these compounds to bind to and block receptors for endogenous transmitter substances. These effects develop acutely. Antagonism at muscarinic cholinoceptors leads to atropine-like effects such as tachycardia, inhibition of exocrine glands, constipation, impaired micturition, and blurred vision. 

Over the course of the past few decades, a number of synthetic atropine-like substances with more spasmolytic and less anticholinergic action and causing fewer side effects have been used clinically in treating stomach ulcers, pylorospasms, and hyperperistaltics. 

Atropine A subtherapeutic dose of atropine has been added to difenoxin to discourage deliberate overdosage. A recommended dose is not likely to cause prominent anticholinergic side effects, but avoid in patients in whom anticholinergic drugs are P.833... 

Eserine blocks acetylcholine esterase. This alkaloid may be used to decrease possible negative side effects connected to the use of other drugs, for example that of atropine. 

Hi-receptor but also at muscarinic cholinoceptors, serotonin receptors, and adrenoceptors. This explains the atropine-like side effects of those drugs. The cationic amphophilic structure of these substances resemble that of antiarrhythmic agents which might explain the arrhythmogenic properties seen with some of these Hi-antagonists. 

C. Atropine will not directly paralyze the respiratory muscles. However, it can prevent the detection of early signs of an overdose of neostigmine, which can quickly progress to a depolarizing block of skeletal muscle and paralysis of the respiratory muscles. Dry mouth, ocular disturbances, and tachycardia are common side effects of atropine given alone, but these effects are less likely to occur with competition between atropine and the increase in the synaptic ACh produced by inhibition of AChE by neostigmine. 

Although atropine and related compounds possess bronchodilator activity, their use is associated with the typical spectrum of anticholinergic side effects (see Chapter 13), and they are no longer used in the treatment of asthma. To improve the clinical utility of anticholinergics, quaternary amine derivatives of atropine were developed. By virtue of their positive charge, these drugs are absorbed poorly across mucosal surfaces and thus produce fewer side effects than atropine, especially when given by inhalation. 

Ipratropium is virtually devoid of the CNS side effects associated with atropine. The most prevalent peripheral side effects are dry mouth, headache, nervousness, dizziness, nausea, and cough. Unlike atropine, ipratropium does not inhibit mucociliary clearance and thus does not promote the accumulation of secretions in the lower airways. 

Geriatric Considerations - Summary Glycopyrrolate does not cross the blood-brain barrier so is less likely to cause the central effects seen with anticholinergics such as atropine. Other anticholinergic side effects such as blurred vision, dry mouth, urinary retention, and constipation do occur and can limit the usefulness of this drug in the older adult. 

Atropine causes dryness of mouth as side effect which is due to its antisecretory effect, and due to this action atropine is used in peptic ulcer. 

Atropine like drugs cause several side effects such as dry mouth, blurred vision, urinary retention, mental confusion, hallucinations etc. 

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