Gastrointestinal effects stimulants

Gastrointestinal effects can be caused by central nervous system stimulation (nausea) or by direct contact (necrosis) with cyanide salts. 

Gastro/ntest/na/Tobacco has gastrointestinal effects that result from parasympathetic stimulation, with a net effect of increased bowel activity (Taylor 1996). Initial exposure to nicotine typically causes nausea, vomiting, and occasionally diarrhea. 

Pseudoephedrine is generally well tolerated in therapeutic doses. Common adverse effects include CNS stimulant effects (e.g., tremor, restlessness, nervousness, irritability) and gastrointestinal effects (e.g., nausea, vomiting, dysgeusia). 

Toxic effects are an extension of terbutaline s pharmacologic activity. Common symptoms include hypertension, tachycardia, arrhythmias, central nervous system stimulation, gastrointestinal effects, and transient electrolyte changes (e.g., hypokalemia). 

Itoh, Z., Suzuki, T., Nakaya, M., Inoue, M., and Mitsuhashi, S. (1984). Gastrointestinal motor-stimulating activity of macrolide antibiotics and analysis of their side effects on the canine gut. Antimicrob. Agents Chemother. 26, 863-869. 

The peptides listed here are not associated with marked increases in gastrointestinal motility. Bethanechol, a muscarinic choUnoceptor agonist, is an effective stimulant of the gut. The answer is (B). 

Normally, dietary tyramine is broken down in the gastrointestinal tract by MAO and is not absorbed. In the presence of MAOI, however, all of its potent sympathomimetic actions are seen. Other side effects of MAOI include excessive CNS stimulation, orthostatic hypotension, weight gain, and in rare cases hepatotoxicity. Because the monoamine oxidase inhibitors exhibit greater toxicity, yet no greater therapeutic response than other, newer agents, clinical use has been markedly curtailed. The primary use for MAOIs is in the treatment of atypical depressions, eg, those associated with increased appetite, phobic anxiety, hypersomnolence, and fatigues, but not melancholia (2). 

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. 

Ipecac is prepared from the dried roots and rhizomes of Cephaelis ipecacuanha (Brot.) A. Rich, and contains the alkaloids emetine [483-18-1] (17) and cephaeJine [483-17-0] (18) in a ratio between 2 1 and 4 1. It has been used extensively in cough preparations and is beheved to act by gastric reflex stimulation. Toxic effects include vomiting, irritation of the gastrointestinal tract, and cardiac arrhythmias (19). Ipecac symp is available over-the-counter in the United States only in 30-mL containers for use as an emetic in treating poisonings. 

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