Confusion anticholinergic drugs

These drugs were developed before levodopa which has largely replaced them, probably because of a lack of modern clinical research. Actually, the adverse effects of anticholinergic drugs (confusion, memory disorders, peripheral anticholinergic effects) and the interindividual variability of their effects considerably limit their use, particularly in subjects over 65 years of age. These compounds are considered to be effective against tremor and are... 

Individuals older than 60 years frequently develop increased sens tivity to anticholinergic drugs and require careful monitoring. Confusion and disorientation may occur. Lower doses may be required. 

The adverse effects of the anticholinergic drugs are due to their antimuscarinic effects in other systems (e.g., cycloplegia, dry mouth, urinary retention, and constipation). Confusion, delirium, and hallucinations may occur at higher doses. 

From the brain-disabling viewpoint, anticholinergic drugs can cause confusion, organic brain syndromes, and psychoses. Far too little attention has been paid to their adverse effects on memory and learning, which can interfere with everyday living, rehabilitation, or school (Marcus et al., 1988 McEvoy, 1987). Furthermore, there is concern that the use of these drugs increases the risk of TD (APA, 1992). 

Anticholinergic drugs can cause vivid and sometimes exotic hallucinations and this has led to their misuse. Plants containing atropine and related substances were used in witches brews in the Middle Ages to conjure up the devil, but even synthetic tertiary amines given in eye-drops and depot plasters containing atropine (SEDA-13, 114) have caused hallucinations. Postoperative confusion... 

Much more common are such sjmptoms as confusion (13% of cases), depression (9% of cases, often requiring antidepressant drugs), and sleep disturbances (20% of cases). Vivid hallucinations are common. Psychotic sjmptoms appear to be more common when enzyme inhibitors are used or anticholinergic drugs given. Panic attacks seem to occur in some 20% of cases during the off phases of an off/on cycle (38). 

Frequently seen adverse reactions to dragp with anticholinergic activity include dry mouth, blurred vision, dizziness, mild nausea, and nervousness. These may become less pronounced as therapy progresses. Other adverse reactions may include skin rash, urticaria (hives), urinary retention, dysuria, tachycardia, muscle weakness, disorientation, and confusion. If any of these reactions are severe, the drug may be discontinued for several days and restarted at a lower dosage, or a different antiparkinsonism drag may be prescribed. 

Because of the anticholinergic action of these agents, use with caution and with appropriate monitoring in patients with glaucoma, obstructive disease of the Gl or GU tract, and in elderly males with possible prostatic hypertrophy. These drugs may have a hypotensive action, which may be confusing or dangerous in postoperative patients. 

Geriatric Considerations - Summary Alkaloids from the belladonna plant contain 3 potent anticholinergics and offer no advantage over other available drugs. Belladonna alkaloids possess potent anticholinergic effects and can cause dry mouth, blurred vision, delirium, confusion, psychosis, and increased risk of falls. This compound has no role in treating the older adult. 

Geriatric Considerations - Summary Dicyclomine is a weak anticholinergic but has the potential to cause adverse effects in the older adult, including urinary retention, hypotension, and confusion. The potential for adverse effects limits the usefulness of this drug for older adults. 

MAO Inhibitors. In contrast to the tricyclics, MAO inhibitors tend to produce CNS excitation, which can result in restlessness, irritability, agitation, and sleep loss. These drugs also produce some central and peripheral anticholinergic effects (e.g., tremor, confusion, dry mouth, urinary retention), but these effects tend to occur in a lesser extent than with the tricyclics (see Table 7-3). Because of the systemic MAO inhibition, excess activity at peripheral sympathetic adrenergic terminals may cause a profound increase in blood pressure, leading to a hypertensive crisis. This situation is exacerbated if other drugs that increase sympathetic nervous activity are being taken... 

Anticholinergics are associated with many side effects including mood change, confusion, hallucinations, drowsiness, and cardiac irregularity.13,39 In addition, blurred vision, dryness of the mouth, nausea/ vomiting, constipation, and urinary retention are fairly common. Antihistamine drugs with anticholinergic properties are also used occasionally (Table 10-2). 

The classic anticholinergic syndrome is remembered as "red as a beet" (skin flushed), "hot as a hare" (hyperthermia), "dry as a bone" (dry mucous membranes, no sweating), "blind as a bat" (blurred vision), and "mad as a hatter" (confusion, delirium). Patients usually have sinus tachycardia, and the pupils are usually dilated (see Chapter 8 Cholinoceptor-Blocking Drugs). There may be agitated delirium or coma. Muscle twitching is common, but seizures are unusual unless the patient has ingested an antihistamine or a tricyclic antidepressant. Urinary retention is common, especially in older men. 

Many different classes of drugs can produce hallucinations when given in toxic doses (e.g. the anticholinergics, such as atropine and scopolamine), but such symptoms are generally associated with confusion and lack of sensory clarity. As such, hallucinations are a component of a toxic psychosis. 

In low dosages scopolamine can produce effects on the CNS, presmnably due to its ability to penetrate the blood-brain barrier. Drowsiness and confusion are frequently reported. Patients also tend to exhibit a higher incidence of idiosyncratic reactions to scopolamine than to other anticholinergic agents, and, hence, it is not the drug of first choice for cycloplegic refraction or treatment of anterior uveal inflammations. Its use is reserved primarily fiar patients who exhibit sensitivity to atropine. 

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