Nausea anticholinergic drugs

Dry mouth, blurred vision, urinary hesitancy, urinary retention, nausea, vomiting, palpitations, and headache are some of die adverse reactions that may be seen witii die use of anticholinergic drug (see Chap. 25). 

Nausea and vomiting Gastric dysmotility (surgery, anticholinergic drugs, diabetic gastroparesis) Rapid infusion of hyperosmolar formula... 

Parenteral overdose produces a cholinergic crisis manifested as abdominal discomfort or cramps, nausea, vomiting, diarrhea, flushing, facial warmth, excessive salivation, diaphoresis, urinary urgency, and blurred vision. If overdose occurs, stop all anticholinergic drugs and immediately administer 0.6-1.2 mg atropine sulfate IM or IV. 

Rebound psychosis or delirium or both have been reported after withdrawal of clozapine (207-212). Clozapine withdrawal has also been associated with nausea, vomiting, diarrhea, headache, restlessness, agitation, and sweating (213,214), which occur as the result of cholinergic rebound and which may respond to anticholinergic drugs (215), and with dystonias and dyskinesias. Delirium and the return of dyskinetic movements can occur within days after clozapine withdrawal. 

Miosis, pain, dim vision, and nausea may be relieved by topical atropine in the eye. Atropine, a cholinergic blocker or anticholinergic drug, is effective in blocking the effects of excess acetylcholine at peripheral muscarinic sites. The usual dose is 2 mg for minor exposures and 6 mg for severe exposures. 

Meclizine is an anticholinergic drug that acts on the CNS to decrease vestibular stimulation and depress labyrinthine activity. It is indicated in the prevention and treatment of nausea, vomiting, and dizziness of motion sickness possibly as effective treatment for vertigo of vestibular dysfunction origin. 

Local instillation of an anticholinergic drug such as atropine or homatropine usually brings relief from the pain and systemic effects (including the nausea and vomiting), but because these drugs cause blurring of vision, they should not be used unless the pain is severe.59... 

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. 

In anesthesia drugs from several groups are used as premedication. Pre-anesthetic medication can decrease the anesthetic doses which otherwise would be required to induce anesthesia and so decrease the risk for adverse effects. Pre-anesthetic medication will increase the rate of induction of anesthesia and can reduce pre-operative pain and anxiety. Drugs include benzodiazepines for sedation and their muscle relaxant properties, opiates for pain relieve and anticholinergics or histamine Hi receptor antagonists against nausea and vomiting. Neuroleptics are also used as premedication for their antiemetic effects. 

Geriatric Considerations - Summary Diphenoxylate is an analog of meperidine and can cause opiate adverse effects. When discontinued, physical dependence and withdrawal symptoms can occur. Adverse GI effects such as constipation, nausea/vomit-ing, and abdominal pain may result from normal doses. Afropine is added to discourage abuse but can cause anticholinergic adverse effects in the older adult. The benefits of f his drug combination for older adulfs are limifed by fhe risk of adverse effects. 

Cyclizine has antimuscarinic properties and is a potent anti-emetic, effective for the control of postoperative and drug-induced nausea and vomiting. It has been used to prevent motion sickness, although diphenhydramine and promethazine are more effective. It is available in oral and parenteral formulations. In contrast to many other first-generation antihistamines sedation is not marked. It is available in tablet form as the hydrochloride and in injectable form as the lactate. Because of its anticholinergic action, blurred vision and dry mouth are associated with clinical doses. When given by rapid intravenous injection tachycardia may be a problem. Meclozine is a related drug which, like cyclizine, is used primarily for motion sickness. 

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 DSM-IV classifies anxiety disorders in children into four categories, namely social anxiety, over-anxious disorder, phobias and separation anxiety. Only separation anxiety, a fear of losing a loved one or a close attachment, has been reasonably well studied from the point of view of drug treatment. School phobia is perhaps the most severe form of separation anxiety and there are several trials to show that imipramine, in daily doses of up to 5mg/kg, is effective. Many patients require drug treatment for at least 6 to 8 weeks before an optimal response is achieved. Frequently, children remain symptom free after a 3M month course of treatment. In addition to the usual anticholinergic effects of imipramine, it should be noted that children are often susceptible to withdrawal symptoms such as nausea and gastrointestinal spasm. This may be reduced if the drug is slowly withdrawn over a 2-week period. 

Many neuroleptics produce withdrawal symptoms that mimic the flu, including emotional upset, insomnia, nausea and vomiting, diarrhea, anorexia and weight loss, and muscle aches (chapter 4). This is particularly strong in drugs that have anticholinergic properties such as Thorazine and Mellaril. 

The major adverse effects of fluoxetine confirm its stimulant profile and its relative lack of anticholinergic actions. The most frequent adverse effects, which occurred in 10-25% of patients, were nausea (25%), nervousness, insomnia, headache, tremor, anxiety, drowsiness, dry mouth, sweating, and diarrhea (10%). Most of these adverse effects occurred early in treatment and seldom led to drug withdrawal. 

Atropine (0.4-0.6 mg intramuscular or intravenous) or other anticholinergic or antiemetic drugs may be used to control nausea and vomiting. 

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