McKenna's Pharmacology for Nursing, 2e

904

P A R T 1 1  Drugs acting on the gastrointestinal system

■ ■ Inspect the skin for evidence of lesions or rash to monitor for adverse reactions. ■ ■ Evaluate neurological status, including orientation and affect, to assess CNS effects of the drug and to plan for protective measures. ■ ■ Assess cardiopulmonary status, including pulse, blood pressure and electrocardiogram (if intravenous use is needed), to evaluate the cardiac effects of the drug. ■ ■ Perform abdominal examination, including assessment of liver, to establish a baseline and rule out underlying medical problems. ■ ■ Monitor the results of laboratory tests, including liver and renal function tests, to predict changes in metabolism or excretion of the drug that might require dose adjustment. ■ ■ Administer oral drug with or before meals and at bedtime (exact timing varies with product) to ensure therapeutic levels when the drug is most needed. ■ ■ Arrange for decreased dose in cases of hepatic or renal dysfunction to prevent serious toxicity. intravenous doses to allow early detection of potentially serious adverse effects, including cardiac arrhythmias. ■ ■ Assess the person carefully for any potential drug–drug interactions if given in combination with other drugs because of the drug effects on liver enzyme systems. ■ ■ Provide comfort, including analgesics, ready access to bathroom facilities and assistance with ambulation, to minimise possible adverse effects. ■ ■ Periodically reorient the person and institute safety measures if CNS effects occur to ensure safety and improve tolerance of the drug and drug effects. ■ ■ Arrange for regular follow-up to evaluate drug effects and the underlying problem. ■ ■ Offer support and encouragement to help people cope with the disease and the drug regimen. ■ ■ Provide teaching regarding drug name, dosage, and schedule for administration; importance of spacing administration appropriately as ordered; need for readily available access to bathroom; signs and symptoms of adverse effects and measures to minimise or prevent them; danger signs that necessitate notifying the healthcare provider immediately; safety measures, such as avoiding driving and asking for assistance when ambulating, to deal with possible effects of dizziness, somnolence or confusion; the need for compliance with therapy to achieve the intended ■ ■ Monitor the person continually if giving Implementation with rationale

results; and the importance of periodic monitoring and evaluation, including laboratory testing, to determine drug effectiveness and to enhance knowledge about drug therapy and to promote compliance.

Evaluation

■■ Agents affecting gastrointestinal secretion include H 2 antagonists, antacids, proton pump inhibitors, GI protectants and prostaglandins. Digestive enzymes replace missing GI enzymes. ■■ Among the most common complaints addressed in clinical practice are GI symptoms. ■■ Increased acid production, decrease in the protective mucus lining of the stomach, infection with Helicobacter pylori bacteria, or a combination of these is the likely cause of peptic ulcers. ■■ H 2 antagonists block the release of acid in response to gastrin or parasympathetic release; adverse effects can include dizziness, confusion, cardiac arrhythmias and galactorrhoea. A ntacids Antacids (Table 57.1) are a group of inorganic chemicals that neutralise stomach acid. Antacids are available over the counter, and many people use them to self-treat a variety of GI symptoms. There is no one perfect antacid (see Adverse effects). The choice of an antacid depends on adverse effect and absorption factors. Available agents are sodium bicarbonate, calcium carbonate, mag- nesium salts and aluminium salts. Therapeutic actions and indications Antacids neutralise stomach acid by direct chemical reaction (see Figure 57.1). They are recommended for the symptomatic relief of upset stomach associated with hyperacidity, as well as the hyperacidity associated with peptic ulcer, gastritis, peptic oesophagitis, gastric ■ ■ Monitor response to the drug (relief of GI symptoms, ulcer healing, prevention of progression of ulcer). ■ ■ Monitor for adverse effects (dizziness, confusion, hallucinations, GI alterations, cardiac arrhythmias, hypotension, gynaecomastia). ■ ■ Evaluate the effectiveness of the teaching plan (person can name drug, dosage, adverse effects to watch for and specific measures to avoid them). ■ ■ Monitor the effectiveness of comfort measures and compliance with the regimen. KEY POINTS