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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;
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
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
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.
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.
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.
