Gastrointestinal Disease

Gastrointestinal disease primarily affects drug absorption (Beliles 2000b). Examples of conditions that affect absorption include diseases affecting gas trointestinal motility, surgical alteration of the gastrointestinal tract (e.g., bypass surgery, G-tube and J-tube placement), short bowel syndrome, and celiac disease. Any conditions that divert blood away from the gastrointestinal tract, for example, congestive heart failure or shock, may also affect absorption. Administration of antacid medications may similarly reduce gastric absorption.

Gastric motility may be affected by a number of general medical conditions and by specific medications. For example, gastric motility is delayed in patients with diabetes mellitus, gastritis, and pyloric stenosis. Anticholinergic medications delay gastric motility. A number of medications are given to increase gastrointestinal motility, including metoclo-pramide and propantheline (Greiff and Rowbotham 1994; Grover and Drossman 2008). Cisapride was a frequently used medication for this indication but was voluntarily removed from the U.S. market in 2000 due to concerns over QTc prolongation. In general, slowed gastrointestinal motility results in better absorption of poorly soluble drugs, and vice versa. Enteric-coated preparations of medications are likely to have increased rates of drug absorption in patients with reduced gastric acidity. Orally administered drugs may be poorly absorbed in patients with malabsorption syndromes. If absorption is an issue, liquid formulations of drugs and alternative routes of administration, including sublingual, intramuscular, and intravenous, may be preferred. Gastrointestinal disease affecting the large intestines generally has little effect because most medications are absorbed more proximally.

Medications with anticholinergic side effects can slow gastrointestinal motility, affecting absorption and causing constipation. By contrast, selective serotonin reuptake inhibitors (SSRIs) increase gastric motility and may cause diarrhea (Trindade et al. 1998). SSRIs have the potential to increase the risk of gastrointestinal bleeding, especially when coad-ministered with NSAIDs (de Abajo et al. 2006; Loke et al. 2008). Using extended- or controlled-release preparations of medications may reduce gastrointestinal side effects, particularly where gastric distress is related to rapid increases in plasma drug concentrations.

Supplements For Diabetics

Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

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