Gastrointestinal function emesis

Disturbances of gastrointestinal function are often accompanied by electrolyte imbalance due to fluid losses by emesis (vomiting), volvulus (dilation), diarrhea, or other perturbations of many varied mechanisms for electrolyte and fluid homeostasis (see... 

Models to identify drug effects on gastrointestinal function should cover gastrointestinal motility, nausea and emesis liability, secretory function (e.g., acidic, ions, hormones), and absorption aspects. Both in vitro and in vivo assessments are available and can be used either in stand-alone SP studies or as specific endpoints integrated into toxicology studies. In addition, novel in sUico tools could also be considered. The choice of approach reflects the focus of a project and may involve isolated cells, organ tissues, and/or whole animals. 

Dopamine is an intermediate product in the biosynthesis of noradrenaline. Furthermore it is an active transmitter by itself in basal ganglia (caudate nucleus), the nucleus accumbens, the olfactory tubercle, the central nucleus of the amygdala, the median eminence and some areas in the frontal cortex. It is functionally important, for example in the extra-pyramidal system and the central regulation of emesis. In the periphery specific dopamine receptors (Di-receptors) can be found in the upper gastrointestinal tract, in which a reduction of motility is mediated, and on vascular smooth muscle cells of splanchnic and renal arteries. Beside its effect on specific D-receptors, dopamine activates, at higher concentrations, a- and -adrenoceptors as well. Since its clinical profile is different from adrenaline and noradrenaline there are particular indications for dopamine, like situations of circulatory shock with a reduced kidney perfusion. Dopamine can dose-dependently induce nausea, vomiting, tachyarrhythmia and peripheral vasoconstriction. Dopamine can worsen cardiac ischaemia. 

Gastrointestinal decontamination with multiple dose activated charcoal is recommended for recent acute ingestion [86] and may be most effective (along with cathartics) for enteric coated salicylate preparations. Induction of emesis with ipecac is no longer recommended [86]. Alkalinization of the urine is recommended for patients with preserved renal function who are unsuitable or do not meet criteria for dialysis [87] and may be of benefit during preparation for hemodialysis. 

If exposure is through ingestion, the victim should seek medical help immediately. Emesis should not be induced. Initial management involves establishment of adequate ventilation and maintenance of adequate respiratory function. Activated charcoal therapy may be used to retard absorption from the gastrointestinal tract. Atropine sulfate alone, or in combination with pralidoxime chloride, can be administered as an antidote. Atropine is initially administered intravenously at a dosage of 1-2 mg kg every 5-10 min until... 

The potential for esophageal or gastrointestinal tract irritation following ingestion suggests that emesis should not be induced. Other measures to prevent absorption may be beneficial. Exposed skin and eyes should be copiously flushed. Liver function and blood glucose must be monitored. 

In the patient who presents with seizures, airway protection and seizure control are primary goals. Disturbances in cardiac rhythm or function also require immediate attention. Ipecac-induced emesis is contraindicated due to the risk of seizures and the resulting potential for aspiration. Gastrointestinal decontamination via administration of activated charcoal should be considered for substantial recent ingestions. Pyridoxine is administered intravenously to all symptomatic and potentially serious asymptomatic overdoses as it provides rapid relief or prevention of severe toxicity, including seizures. The pyridoxine dosage is... 

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