Coreg, or carvedilol, is an antihypertensive drug that belongs to the class of medications called beta-blockers. It is used for treatment of moderate to severe heart failure, in which the patient does not receive enough oxygen in the heart or experiences inflammation of the heart muscle. Coreg may also be used in patients who have a left chamber dysfunction in the heart. Patient with high blood pressure may also be prescribed this medication. Coreg is safe and effective; however, it may be contraindicated in some individuals.
Asthma and COPD
Coreg functions on the beta cells in the heart to decrease oxygen supply in heart failure and to decrease the blood pressure by allowing the vessels to dilate. Coreg also functions on beta cells found in other parts of the body, including the lungs, liver, pancreas and smooth muscle. Normally, beta receptors in the lungs lead to a widening of the air passages and dilation of vessels. Coreg blocks these receptors and may cause constriction of the airways and surrounding vessels. In patients with diseases such as asthma and chronic obstructive pulmonary disease, or COPD, airflow is obstructed, and spasms on the airway may occur. Coreg may cause a worsening of symptoms and may be life-threatening, according to "Pharmacotherapy: A Pathophysiologic Approach." Patients with these diseases should not use Coreg, and they should inform their physician of any medical problems to avoid complications.
Bronchitis
Bronchitis is an inflammation of the mucous membranes of the airways. It is typically caused by a virus but may be due to a bacteria or inhaled chemical that causes irritation. Symptoms include nasal congestion, cough, muscle aches and wheezing, and treatment is geared towards relieving symptoms. Coreg may worsen these symptoms by causing constriction of the airways. Patients should immediately inform a physician if these symptoms develop. The drug should be discontinued and restarted when the patient is better.
Liver Disease
Coreg is broken down in the body by the liver. Patients with liver impairment may accumulate the medication in the body, leading to toxicity. Signs and symptoms of toxicity include seizures, decreased breathing rate, decreased sugar levels, decreased blood pressure and cardiac arrest, according to RxList.com. If the patient experiences any of these symptoms, he should seek emergency medical care.
Serious Heart Conditions
Coreg is contraindicated in patients with a serious heart condition, explains the "Drug Information Handbook." Patients with a slow heart rate, who do not have a pacemaker, should not use Coreg. Patients with cardiogenic shock, which occurs when the heart is unable to pump enough blood to supply the body, must not take Coreg. Coreg is also contraindicated in patients with sick sinus syndrome, a malfunction of the heart's natural pacemaker that leads to abnormal heart rhythm. The use of Coreg and intravenous ionotropes in patients with heart failure is not recommended. These patients should discontinue the intravenous medication before starting Coreg.
Allergy
Coreg must not be administered to patients with a history of a serious allergic reaction to this medication or any medication containing Coreg. If the patient develops an allergic reaction, such as itchiness, swelling of the mouth or lips and difficulty breathing, she should immediately call a physician and seek medical attention.
References
- "Pharmacotherapy: A Pathophysiologic Approach"; Joseph T. Dipiro, Robert L. Talbert, et al.; 2008
- RxList.com: Coreg
- "Drug Information Handbook"; Charles F. Lacy, Lora L. Armstrong, et al.; 2009
