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 hydralazine, the following should be considered:

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

Pregnancy—Although hydralazine often is used to reduce high blood pressure in pregnant women, extensive studies of hydralazine in pregnant women have not been done. However, blood problems and other problems have been reported in infants of mothers who took hydralazine during pregnancy. In addition, studies in mice have shown that high doses of hydralazine cause birth defects (cleft palate, defects in head and face bones). These birth defects also occurred in rabbits, but did not occur in rats. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—Hydralazine passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Although there is no specific information comparing use of hydralazine in children with use in other age groups, this medicine is not expected to cause different side effects or problems in children than it does in adults. However, the oral solution contains aspartame, which is converted to phenylalanine in the body. Children with phenylketonuria cannot process phenylalanine and high levels of this substance in body fluids may cause brain damage.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing use of hydralazine in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in 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 hydralazine, it is especially important that your health care professional know if you are taking the following:

• Diazoxide (e.g., Proglycem)—Effect on blood pressure may be increased

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

• Heart or blood vessel disease or
• Stroke—Lowering blood pressure may make problems resulting from these conditions worse

• Kidney disease—Effects may be increased because of slower removal of hydralazine from the body
• Phenylketonuria—The oral solution of hydralazine contains aspartame, which is converted to phenylalanine in the body. Patients with phenylketonuria cannot process phenylalanine and high levels of this substance in body fluids may cause brain damage