(LifeWire) - Primacor (milrinone) is a medication used to treat heart failure. Milrinone belongs to a class of medications known as inotropes used to treat heart failure by helping the heart contract, which allows the heart to pump blood more effectively. Milrinone also widens blood vessels, making it easier for the heart to move the blood through the arteries. (There are also other inotropes, which include dobutamine and dopamine.)
Milrinone is given to patients orally and as an intravenous injection or continuous intravenous infusion. It is usually used in cases of acute heart failure, that is, heart failure that occurs in a matter of minutes or hours. Chronic heart failure, by contrast, is a long-term condition that is managed with different drugs. Milrinone is not recommended for long-term use. That is because according to several studies, it has been associated with hypotension (low blood pressure), arrhythmia (irregular heartbeat) and a higher incidence of hospitalization and death than was seen with other medications.
Patients with heart failure who are awaiting a heart transplant may also benefit from milrinone. These patients can be treated at home while waiting for a transplant operation when appropriate measures are taken, such as medication to prevent arrhythmia. There is some evidence that milrinone may be beneficial when combined with beta blockers for patients with advanced heart failure.
Side effects of milrinone may include hypotension, blurred vision, headache and diarrhea. A healthcare provider should be contacted immediately if any of the following conditions occur when taking milrinone: arrhythmia, fainting, dizziness, rash, chest pain or pressure, unusual bleeding or bruising or any signs of an allergic reaction, such as swelling, unusual skin color, fever, itching or wheezing.
In addition to its use in treating heart failure, milrinone has also been studied for its association with atrial fibrillation after heart surgery. Atrial fibrillation occurs when the two upper chambers of the heart (the atria) beat irregularly; it is a serious and potentially life-threatening condition. Milrinone has been shown to be a risk factor for atrial fibrillation when used after heart surgery.
Read more about treating heart failure here.
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