From the FDA Drug Label
Cardiovascular Cold extremities; arterial insufficiency, usually of the Raynaud type; palpitations; congestive heart failure; peripheral edema; and hypotension have been reported in about 1 of 100 patients Edema is listed as a potential adverse reaction to metoprolol.
- Peripheral edema has been reported in about 1 of 100 patients 1
From the Research
Metoprolol can cause edema in some patients, as evidenced by case reports and studies, although the exact mechanism and frequency are not well-established. The edema associated with metoprolol is typically mild to moderate and results from the drug's effects on blood vessel tone and fluid retention. Beta-blockers like metoprolol can decrease cardiac output and peripheral vascular resistance, which may lead to pooling of fluid in the extremities. Additionally, they can interfere with the renin-angiotensin-aldosterone system, potentially causing sodium and water retention 2.
Some studies have reported cases of edema associated with metoprolol use, such as a case of angioedema following intravenous administration of metoprolol 2. However, other studies have found that metoprolol can actually reduce water retention and improve urine excretion when used in combination with other medications, such as fenoterol 3.
It's essential to note that the majority of the provided evidence does not directly address the question of metoprolol causing edema, with the exception of a few case reports and studies 4, 2. The most relevant and recent study that discusses edema in the context of beta-blocker use is not directly related to metoprolol but to pramipexole, a dopamine agonist 5.
In clinical practice, if a patient experiences significant swelling while taking metoprolol, they should not discontinue the medication abruptly, as this can lead to rebound hypertension or other cardiac issues. Instead, they should contact their healthcare provider, who may adjust their dosage, add a diuretic to help eliminate excess fluid, or consider switching to an alternative medication if the edema is problematic. Elevating their legs when sitting and reducing salt intake may help manage mild edema while continuing necessary beta-blocker therapy.
In terms of the provided evidence, the study from 1994 2 is the most relevant to the question, as it reports a case of angioedema associated with metoprolol use. However, it's crucial to consider the overall clinical context and the potential benefits and risks of metoprolol therapy when making treatment decisions. The decision to use metoprolol should be based on a thorough evaluation of the patient's individual risk factors and medical history, as well as careful monitoring for potential side effects, including edema.