From the Guidelines
A patient who experienced angioedema with lisinopril can typically tolerate losartan safely, as indicated in the 2018 guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.
Key Considerations
- Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor, while losartan is an angiotensin receptor blocker (ARB), and they work through different mechanisms.
- ACE inhibitor-induced angioedema occurs due to increased bradykinin levels when ACE is blocked, whereas ARBs do not significantly affect bradykinin metabolism.
- According to the guideline, patients with a history of angioedema with an ACE inhibitor can receive an ARB beginning 6 weeks after ACE inhibitor is discontinued 1.
Important Points to Note
- The patient should be monitored closely when starting losartan, especially during the first few weeks of treatment.
- Initial symptoms of angioedema include facial swelling, particularly around the lips, tongue, or throat, and the patient should be instructed to seek immediate medical attention if these occur.
- Starting with a lower dose of losartan and gradually increasing it may be a prudent approach for these patients.
Mechanism and Safety
- The different mechanisms of action between ACE inhibitors and ARBs suggest that the risk of angioedema with losartan is low, but not negligible.
- As stated in the guideline, do not use losartan if the patient has a history of angioedema with ARBs, but patients with a history of angioedema with an ACE inhibitor can receive an ARB beginning 6 weeks after ACE inhibitor is discontinued 1.
From the FDA Drug Label
The following additional adverse reactions have been reported in postmarketing experience with losartan. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency reliably or to establish a causal relationship to drug exposure: Hypersensitivity: Angioedema, including swelling of the larynx and glottis, causing airway obstruction and/or swelling of the face, lips, pharynx, and/or tongue has been reported rarely in patients treated with losartan; some of these patients previously experienced angioedema with other drugs including ACE inhibitors.
Key Points:
- Angioedema has been reported rarely in patients treated with losartan.
- Some patients who experienced angioedema with losartan had previously experienced angioedema with ACE inhibitors, such as lisinopril.
- There is no guarantee of tolerance: a patient who had angioedema on lisinopril may still experience angioedema on losartan 2.
- Caution is advised when prescribing losartan to patients with a history of angioedema on ACE inhibitors.