4.14 Beta-2 Antagonists
Propranolol is a nonselective Beta-2 antagonist.
Mechanism of Action: Propranolol is a nonselective beta-blocker because of its inhibition of both Beta-1 and Beta-2 receptors.
Indications: Propranolol is used to treat high blood pressure, angina, various heart dysrhythmias (to lower the heart rate), essential tremors, and in migraine prevention. It is prescribed after a client experiences a myocardial infarction to reduce mortality by decreasing heart workload. It is also used for the management of panic associated with panic disorder and post-traumatic stress disorder (PTSD).
Nursing Considerations: Nonselective beta-blockers must be used cautiously with clients who have coexisting asthma or chronic obstructive pulmonary disease (COPD) because of the effects on Beta-2 receptors that could potentially cause bronchoconstriction. It can also mask symptoms of hypoglycemia in diabetics. Use with caution in clients with impaired hepatic or renal function. Give immediate-release (IR) formulations on an empty stomach. Do not crush extended-release (ER) formulations. Propranolol ER is not considered a simple milligram-for-milligram substitute for conventional propranolol. Check blood pressure and apical pulse before giving drug; withhold and notify provider if apical pulse is less than 60 beats per minute or systolic blood pressure is less than 100 mm Hg, unless other parameters are provided. During IV administration, monitor blood pressure, ECG, and heart rate according to agency policy.
Side Effects/Adverse Effects: The most serious adverse effects include bronchoconstriction, hypotension, bradycardia, and signs of worsening heart failure. Other adverse effects are similar to selective beta-blockers like metoprolol.
Boxed Warning: Abrupt withdrawal of this drug may cause exacerbation of angina or a myocardial infarction. To discontinue this drug, gradually reduce dosage over 1 to 2 weeks.
Health Teaching & Health Promotion: Clients should be instructed to follow the medication dosing regimen. Stopping medication therapy abruptly may cause life-threatening arrhythmias. Clients should be instructed on how to self-assess pulse and blood pressure to evaluate medication effectiveness. The medication may cause increased susceptibility to orthostatic blood pressure changes and increased sensitivity to cold.[1]
Now let’s take a closer look at the medication grid on propranolol in Table 4.14.[2]
Table 4.14 Propranolol Medication Grid
Class/Subclass |
Prototype/Generic |
Nursing Considerations |
Therapeutic Effects |
Side/Adverse Effects |
|---|---|---|---|---|
| Beta-2 Antagonist | Nonselective Beta-2 blocker: | Contraindicated in clients with asthma, COPD, or bradycardia
Use cautiously in clients who have diabetes mellitus because drug masks some symptoms of hypoglycemia Use with caution in clients with impaired hepatic or renal function Give immediate-release formulations on an empty stomach Do not crush ER formulations Check BP and apical pulse before giving drug; withhold and notify provider if apical pulse is less than 60 or systolic blood pressure is less than 100 unless other parameters are provided During IV administration, monitor blood pressure, ECG, and heart rate according to agency policy Boxed Warning: Abrupt withdrawal of drug may cause exacerbation of angina or myocardial infarction. To discontinue drug, gradually reduce dosage over 1 to 2 weeks |
Decrease blood pressure and heart rate
Prevent migraines Manage tremors |
Most serious:
-Bronchoconstriction -Hypotension -Bradycardia -Worsening heart failure Other adverse effects similar to metoprolol |
- uCentral from Unbound Medicine. https://www.unboundmedicine.com/ucentral ↵
- This work is a derivative of DailyMed by U.S. National Library of Medicine in the Public Domain. ↵