Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For carvedilol, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to carvedilol. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Carvedilol has not been studied in pregnant women. However, studies in animals have shown that large doses of carvedilol can cause decreased body weight and skeletal problems in rat fetuses. Before taking this medicine, make sure your doctor knows if you are pregnant or may become pregnant.

Breast-feeding—It is not known if carvedilol passes into breast milk; however, it passes into the milk of lactating rats. Because nursing infants may have a serious reaction to carvedilol, breast-feeding is not recommended in women who are taking this medicine.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of carvedilol in children with use in other age groups.

Older adults—Although this medicine has not been shown to cause different side effects or problems in older people than it does in younger adults, blood levels of carvedilol may be increased in the elderly. Elderly patients also may experience dizziness more frequently than will younger adults.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking carvedilol, it is especially important that your health care professional know if you are taking any of the following:

• Antidiabetic agents, sulfonylurea (acetohexamide [e.g., Dymelor], chlorpropamide [e.g., Diabinese], gliclazide [e.g., Diamicron], glipizide [e.g., Glucotrol], glyburide [e.g., DiaBeta, Glynase, or Micronase], tolazamide [e.g., Tolinase], or tolbutamide [e.g., Orinase]) or
• Insulin—Carvedilol may further decrease blood sugar levels

• Calcium channel blocking agents, especially diltiazem (e.g., Cardizem) or verapamil (e.g., Calan)—Carvedilol may make side effects of these medicines worse

Other medical problems—The presence of other medical problems may affect the use of carvedilol. Make sure you tell your doctor if you have any other medical problems, especially:

• Allergic reaction, severe (that involved facial swelling and/or difficulty breathing), history of or
• Asthma or
• Related bronchospastic conditions, other—Carvedilol may cause a greater reaction to substances that aggravate these conditions and less of a response to treatment of the reaction

• Angina (severe chest pain)—Carvedilol may provoke chest pain

• Bronchial conditions, nonallergic or
• Bronchitis, chronic or
• Emphysema—Carvedilol may aggravate these conditions

• Bradycardia (unusually slow heartbeat) or other heart rate problems or
• Heart or blood vessel disease—Carvedilol may make problems resulting from these conditions worse

• Diabetes mellitus (sugar diabetes) or
• Low blood sugar (hypoglycemia)—Carvedilol may aggravate low blood sugar (hypoglycemia) levels caused by insulin and may delay recovery of blood sugar levels; in patients with diabetes and heart failure, carvedilol may further increase blood sugar levels; in addition, if your diabetes medicine causes your blood sugar to be too low, beta-blockers may cover up some of the symptoms (fast heartbeat)

• Kidney disease or
• Liver disease—Effects of carvedilol may be increased because of slower removal from the body

• Overactive thyroid—Carvedilol may cover up symptoms of this condition, such as a fast heartbeat; suddenly stopping carvedilol may provoke symptoms of this condition