Gastrointestinal motility changes

The physiological changes and other aspects in the elderly makes this even more complicated. Example of this is decreased stomach acidity decreased motility decreased blood-flow to liver and gastrointestinal tract changed pharmacokinetics and -dynamics polypharmacy swallowing problems bad nutritional status and lack of documentation. 

Absorption Decreased absorptive surface Decreased splanchnic blood flow Increased gastric pH Altered gastrointestinal motility Little change in absorption with age... 

Figure 6.4 Types of intestinal motility patterns. Segmentation, tonic contraction, and peristalsis are the three major types of motility patterns observed in the gut. Each serves a specific function for digestion and processing of luminal contents. From E.B. Chang, M.D.Sitrin and D.D.Black (1996) Gastrointestinal motility and neurophysiology. Gastrointestinal, Hepatobiliary, and Nutritional Physiology, Lippincott-Raven, Philadelphia, pp. 27-51...

To determine the safety of using lithium chloride dilution to measure cardiac output, the pharmacokinetic and toxic effects of intravenous lithium chloride have been studied in six conscious healthy Standardbred horses (527). The mean peak serum concentration was 0.56 mmol/1. There were neither toxic effects nor significant changes in laboratory studies, electrocardiograms, or gastrointestinal motility. Three horses had increased urine output. 

Opioids share related pharmacologic attributes and exert a profound effect on the CNS and gastrointestinal tract. Mood changes, sedation, respiratory depression, nausea, vomiting, decreased gastrointestinal motility, dependence, and tolerance are evident in varying... 

Thompson, D. G., Archer, L., Benson, M., Green, W., Hardy, R., and Wingate, D. L., 1979, Variation in the glucose tolerance test with normal changes in fasting upper gastrointestinal motility, Clin. Set 57 25P. 

Major gastrointestinal effects include decreased gut motility and changes in secretion of gastric and intestinal fluids. Morphine and most p receptor agonists cause pupillary constriction. Some tolerance to this effect may develop, but addicts with high opioid levels will still have miosis. Respiratory depression is the usual cause of death from opioid overdose. 

A summary of how physiological factors affect the dissolution rate is given in Table 21.2. The effective surface area will be affected by the wetting properties of the bile acids and other surface-active agents in the gastrointestinal tract. The dif-fusivity of a drug molecule in the intestinal juice will be altered by changes in viscosity that are induced, for instance, by meal components. An increased dissolution rate could be obtained at more intense intestinal motility patterns or increased... 

Gastrointestinal discomfort is not unusual in patients receiving chloroquine, and diarrhea can occur. Changes in intestinal motility may be to blame intramuscular injection of chloroquine caused a shortened orofecal time in the five cases in which this was measured. Overdosage can cause vomiting. 

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