McKenna's Pharmacology for Nursing, 2e

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P A R T 6  Drugs acting on the endocrine system

Pharmacokinetics Desmopressin and vasopressin are rapidly absorbed and metabolised; they are excreted in the liver and kidneys. Desmopressin is available for oral, IV, subcutaneous and nasal administration. Vasopressin is administered by subcutaneous or intramuscular injection. Contraindications and cautions Desmopressin and vasopressin is contraindicated with any known allergy to the drug or its components to avoid potential hypersensitivity reactions or with severe renal dysfunction, which could alter the effects of the drug . Caution should be used with any known vascular disease because of its effects on vascular smooth muscle; Teach person about drug therapy, including drug name, dosage, adverse effects, precautions and warning signs of serious adverse effects to report. Monitor blood pressure and pulse rate and adjust dosage as needed. Evaluation Evaluate drug effects, including decrease in signs and symptoms being treated. Monitor for adverse effects: CV effects—tachycardia, heart failure; CNS—confusion, dreams; urinary retention; GI effects—constipation; visual blurring, photophobia. CNS: orientation, affect, reflexes, vision Skin: colour, lesions, texture, sweating GU: urinary output, bladder tone GI: abdominal examination Respiratory: respiratory rate, adventitious sounds Implementation Ensure safe and appropriate administration of the drug. Provide comfort and safety measures, such as physical assistance or raised side rails if B.T. is hospitalised; temperature control; dark eyeglasses; small, frequent meals; artificial saliva, fluids; sugarless lozenges, mouth care; and bowel program. Provide support and reassurance to deal with drug effects, discomfort and GI effects. CARE GUIDE FOR B.T.: DIABETES INSIPIDUS AND POSTERIOR PITUITARY HORMONES Assessment: History and examination Assess for allergies to any anticholinergic agent and other drugs. Also assess for a history of chronic obstructive pulmonary disease, narrow-angle glaucoma, myasthenia gravis, bowel or urinary obstruction, pregnancy or breastfeeding, tachycardia, and recent GI or urinary tract surgery. Focus the physical assessment on the following: CV: Blood pressure, pulse rate, peripheral perfusion, electrocardiogram

Monitor for drug–drug interactions as indicated for each drug. Evaluate the effectiveness of teaching program and comfort and safety measures. TEACHING FOR B.T. • The anterior pituitary hormone desmopressin or antidiuretic hormone acts to promote the resorption of water in your kidneys, replacing the antidiuretic hormone that you are missing in your body. This lack of antidiuretic hormone is the cause of your diabetes insipidus. This drug will replace the missing hormone. This drug also causes your blood vessels to contract and may increase the activity of your GI tract. Some of the following adverse effects may occur: • Tremor, dizziness, vision changes: If these occur, you should avoid driving a car, operating dangerous machinery or performing any other tasks that require alertness. • GI cramping, passing of gas: Eating small, frequent meals may help. • Nasal irritation, development of lesions: Proper administration of the drug will decrease this effect. • Use caution to administer the nasal solution correctly. Sit upright and press a finger over one nostril to close it. Hold the spray bottle upright and place the tip of the bottle about 1.5 cm) into the open nostril. A firm squeeze on the bottle will deliver the drug. Do not use excessive force when squeezing the bottle. Do not tip your head back during administration. • Tell any doctor, nurse or other healthcare provider involved in your care that you are taking this drug. • Watch for any signs of water intoxication (drowsiness, light-headedness, headache, seizures, coma) and report this to your healthcare provider immediately. • Report any nasal pain or runny nose, which might indicate that you are not administering the drug correctly. • Keep this drug, and all medications, out of the reach of children. Do not share this drug with other people.

Safe medication administration

Administering a nasal spray Instruct the person to sit upright and press a finger over one nostril to close it. Then, with the spray bottle held upright, have the person place the tip of the bottle about 1.5 cm into the open nostril. A firm squeeze should deliver the drug to the desired mucosal area for absorption. Caution the person not to use excessive force and not to tip the head back because these actions could result in ineffective administration.

epilepsy; asthma; and with hyponatraemia, which could be exacerbated by the effects of the drug. This drug should not be used during pregnancy because of the