Cholinergic agents, adverse effects

Intranasal anticholinergic agents (e.g., ipratropium) reduce the severity and duration of rhinorrhea but have no effect on other nasal symptoms.11,12,21 Ipratropium reduces cholinergic hyperreactivity and cholinergically mediated histamine- and antigen-induced secretion. Intranasal ipratropium acts locally, with only minimal systemic absorption. Clinical trials demonstrated that ipratropium bromide 0.3% reduced rhinorrhea in adults and children with PAR.11,12 Intranasal ipratropium is an option for patients in whom rhinorrhea is refractory to topical intranasal corticosteroids and/or antihistamines.8,12 Intranasal ipratropium is available only by prescription, and the dose is two sprays nasally two to three times daily.15 Adverse effects are minimal, but dry nasal membranes have been reported.11,12... 

A. Mechanism of Action. BZ (3-quinuclidinyl benzilate) is a cholinergic blocking agent that at single doses of less than 1 mg produces delirium lasting several days. No permanent adverse effects have been reported from clinical studies. BZ is effective by all routes of administration, but its effectiveness percutaneously (when mixed with a suitable solvent) is limited, so that route is not likely to be used. 

These agents block the acetylcholine muscarinic receptors, centrally and peripherally, thereby decreasing cholinergic activity and alleviating adverse effects such as acute dystonia and parkinsonism. The main drugs used for this purpose are benztropine, biperidone, procyclidine, and trihexphenidyl. 

Adverse reactions with donepezil include nausea, vomiting, and diarrhea. These are typical cholinergic side effects to expect with all of the cholinesterase inhibitors. Table 32-6 compares the major side effects for all of the approved agents for Alzheimer s disease.34-38... 

Adverse reactions to contrast agents have been linked to an in vivo interaction with enzymes involved in cholinergic activity. However, experimental results on this topic are conflicting. In a study of the in vivo effects of the non-ionic... 

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