C H A P T E R 3 1
Adrenergic blocking antagonists
481
DISCUSSION
Propranolol, a non-selective beta-blocker, was prescribed
to decrease the tremor he was experiencing. The exact
action of this drug to decrease the tremor is thought to
be related to its membrane-stabilising properties. The
desired therapeutic effect is the reduction of the tremor,
but all of the beta-blocking effects will occur and need to
be monitored. He did well on the drug until pollen season
arrived. That is because propranolol, a non-selective beta-
blocker, prevented the compensatory bronchodilation
that occurs when the SNS is stimulated. When the pollen
reacted with M.R.’s airways, causing them to swell and
become narrower, his swollen bronchial tubes were
unable to allow air to flow through them. The result
was bronchial constriction and respiratory distress that,
in M.R.’s case, progressed to a respiratory arrest. Before
he began taking propranolol, M.R. probably had been
effectively compensating for the swelling of the bronchi
through bronchodilation and had never experienced
such a reaction. There are few other drugs for treating
essential tremor. M.R. and his healthcare providers will
need to decide whether the benefit that the drug has
brought to him is worth the potential for adverse effects.
They might be able to suggest additional drugs to deal
with the seasonal allergic reactions to make the use of the
propranolol safer for M.R.
M.R. may want to discuss this frightening incident
with his healthcare provider. He also may want to include
his family in this discussion. It should be stressed that
he did so well up to this point because he had not
been exposed to pollen and therefore had not had the
problem that brought him into the hospital this time. M.R.
probably never reported the occurrence of hay fever to
his healthcare provider when the drug was prescribed
because it had never been a problem and probably did not
seem significant to him. M.R. and his family should receive
support and be encouraged to talk about what happened
and how they reacted to it. It is normal to feel frightened
and unsure when a loved one is in distress. They should be
involved in the discussion of what medical regimen would
be most appropriate for M.R. at this point.
CARE GUIDE FOR M.R.: PROPRANOLOL
Assessment: History and examination
Review the person’s history for allergy to propranolol, HF,
shock, bradycardia, heart block, hypotension, COPD,
thyroid disease, diabetes, respiratory impairment, and
concurrent use of barbiturates, non-steroidal anti-
inflammatory drugs, piroxicam, sulindac, lignocaine,
cimetidine, phenothiazines, clonidine, theophylline and
rifampicin.
Focus the physical examination on the following:
CV: blood pressure, pulse, peripheral perfusion, ECG
CNS: orientation, affect, reflexes, vision
Skin: colour, lesions, texture
GU: urinary output, sexual function
GI: abdominal, liver evaluation
Respiratory: respirations, adventitious sounds
Implementation
Ensure safe and appropriate administration of the drug.
Provide comfort and safety measures: assistance/side rails;
temperature control; rest periods; mouth care; small,
frequent meals.
Monitor blood pressure, pulse, and respiratory status
throughout drug therapy.
Taper the drug gradually if it is to be discontinued to
decrease the risk of severe hypertension, MI or stroke
related to abrupt withdrawal.
Provide support and reassurance to deal with drug effects
and discomfort, sexual dysfunction and fatigue.
Provide teaching regarding drug name, dosage, side effects,
precautions and warning signs to report.
Evaluation
Evaluate drug effects: blood pressure within normal limits,
decrease in essential tremors, stabilised cardiac rhythm.
Monitor for adverse effects: CV effects: HF, block; dizziness,
confusion; sexual dysfunction; GI effects; hypoglycaemia;
respiratory problems.
Monitor for drug–drug interactions as indicated.
Evaluate the effectiveness of the teaching program.
Evaluate the effectiveness of comfort and safety measures.
TEACHING FOR M.R.
• The drug that has been prescribed for you, propranolol,
is a non-selective beta-adrenergic blocking agent. A
beta-adrenergic blocking agent works to prevent certain
stimulating activities that normally occur in the body in
response to such factors as stress, injury or excitement.
It stabilises certain nerve membranes, which helps to
decrease your tremor.
You should learn to take your pulse and monitor it daily,
writing the pulse rate on the calendar. Your current pulse
rate is 82 beats/minute.
• Never discontinue this medication suddenly. If you
find that your prescription is running low, notify your
healthcare provider at once. This drug needs to be
tapered over time to prevent severe reactions when its
use is discontinued. Some of the following adverse effects
may occur:
•
Fatigue, weakness
: Try to stagger your activities
throughout the day to allow rest periods.
•
Dizziness, drowsiness
: If these should occur, take care to
avoid driving, operating dangerous machinery or doing
delicate tasks. Change position slowly to avoid dizzy
spells.
•
Change in sexual function
: Be assured that this is a drug
effect and discuss it with your healthcare provider.
