Diarrhea anticholinergics

SSRIs are widely used for treatment of depression, as well as, for example, panic disorders and obsessive—compulsive disorder. These dmgs are well recognized as clinically effective antidepressants having an improved side-effect profile as compared to the TCAs and irreversible MAO inhibitors. Indeed, these dmgs lack the anticholinergic, cardiovascular, and sedative effects characteristic of TCAs. Their main adverse effects include nervousness /anxiety, nausea, diarrhea or constipation, insomnia, tremor, dizziness, headache, and sexual dysfunction. The most commonly prescribed SSRIs for depression are fluoxetine (31), fluvoxamine (32), sertraline (52), citalopram (53), and paroxetine (54). SSRIs together represent about one-fifth of total worldwide antidepressant unit sales. 

The Class I agents have many similar side effects and toxicities. The anticholinergic side effects include dry mouth, constipation, and urinary hesitancy and retention. Common gastrointestinal (GI) side effects include nausea, vomiting, diarrhea, and anorexia. Cardiovascular adverse effects are hypotension, tachycardia, arrhythmias, and myocardial depression, especially in patients with congestive heart failure. Common central nervous system (CNS) side effects are headache, dizziness, mental confusion, hallucinations, CNS stimulation, paraesthesias, and convulsions. 

Sedation, anticholinergic effects (dry mouth, dry eyes, urinary retention), nausea, nasal congestion, blurred vision, orthostatic hypotension, lethargy, confusion, constipation, diarrhea... 

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. 

The SSRIs produce fewer sedative, anticholinergic, and cardiovascular adverse effects than the TCAs and are less likely to cause weight gain than the TCAs. The primary adverse effects include nausea, vomiting, diarrhea, headache, insomnia, fatigue, and sexual dysfunction. A few patients have anxiety symptoms early in treatment. 

These drugs have weaker anticholinergic activity than atropine however, they have a significantly more expressed antispastic action. They are used for treating so-called irritable bowel syndrome and diarrhea. 

Cyclizine exhibits antihistamine and anticholinergic action and is used for vomiting and diarrhea. The exact mechanism of action is not known. Synonyms of this drug are marezine and migril. 

Diphenoxylate (marketed in combination with atropine as Lomotil in the United States) is chemically related to both analgesic and anticholinergic compounds. It is as effective in the treatment of diarrhea as the opium derivatives, and at the doses usually employed, it has a low incidence of central opioid actions. Diphenoxylate is rapidly metabolized by ester hydrolysis to the biologically active metabolite difenoxylic acid. Lomotil is recommended as adjunctive therapy in the management of diarrhea. It is contraindicated in children under 2 years old and in patients with obstructive jaundice. Adverse reactions often caused by the atropine in the preparation include anorexia, nausea, pruritus, dizziness, and numbness of the extremities. 

Of particular importance in the geriatric patient Anticholinergic effects, delirium, confusion, drowsiness, agitation, headaches, diarrhea, gynecomastia... 

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. 

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. 

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. 

The use of cisapride and its benefit to harm balance in children has been reviewed (25). Overall it is well tolerated. The most common adverse effects are diarrhea, abdominal cramps, borborygmi, and colic. Serious adverse events are rare and include isolated cases of extrapyramidal reactions, seizures in epileptic patients, cholestasis, QT interval prolongation and ventricular dysrhythmias, anorexia, and enuresis. Interactions of cisapride with other drugs are similar to those reported in adults. Co-administration of drugs that inhibit CYP3A4, such as imidazoles, macrolide antibiotics, the antidepressant nefazodone, and protease inhibitors such as ritonavir, are contraindicated. Furthermore, co-administration of anticholinergic drugs can compromise the beneficial effects of cisapride. 

Nausea, vomiting, and diarrhea in response to procainamide are common with dosages of 4 g/day or more (32). Pseudo-obstruction has been attributed to the use of a modified-release formulation of procainamide, perhaps due to its anticholinergic effects (33). 

Medication Sedation Agitation/ insomnia Anticholinergic effects Orthostasis Gl effects (nausea/diarrhea) Sexual dysfunction Weight gain... 

Side effects/ adverse reactions Frequent Nausea, vomiting, diarrhea, anorexia Occasional Abdominal pain, insomnia, depression, headache, dizziness, fatigue, rhinitis Rare Tremors, constipation, confusion, cough, anxiety, urinary incontinence Adverse/toxic Overdose can cause cholinergic crises (increased salivation, lacrimation, urination, defecation, bradycardia, hypotension, increased muscle weakness). Treatment aimed at general supportive measures, use of anticholinergics (e.g., atropine)... 

Most experts agree that the SSRIs are better tolerated than clomipramine. The SSRIs are less likely to cause cardiovascular, sedative, anticholinergic, and weight gain side effects. Clomipramine is less likely than the SSRIs to cause insomnia, akathisia, nausea, and diarrhea. Side effects may be more severe when larger doses are used and with faster dose escalation. Tolerance to adverse effects often develops over 6 to 8 weeks of treatment, and tolerance is more fikely to develop to nausea, diarrhea, sedation, diminished libido and/or orgasm, anxiety, restlessness, insomnia, and anticholinergic side effects than to akathisia. ... 

Disopyramide Anticholinergic effects (urinary retention, aggravation of glaucoma, constipation), hypotension, heart failure, tachyarrhythmias, torsade de pointes, heart block, nausea, vomiting, diarrhea, hypoglycemia, nervousness... 

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