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 carbonic anhydrase inhibitors, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to carbonic anhydrase inhibitors, sulfonamides (sulfa drugs), or thiazide diuretics (a type of water pill). Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Carbonic anhydrase inhibitors have not been studied in pregnant women. However, studies in animals have shown that carbonic anhydrase inhibitors cause birth defects. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—Carbonic anhydrase inhibitors may pass into the breast milk. These medicines are not recommended during breast-feeding, because they may cause unwanted effects in nursing babies. It may be necessary for you to use another medicine or to stop breast-feeding during treatment. Be sure you have discussed this with your doctor.

Children—Although there is no specific information comparing use of carbonic anhydrase inhibitors in children with use in other age groups, these medicines are not expected to cause different side effects or problems in children than they do in adults.

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 carbonic anhydrase inhibitors in the elderly with use in other age groups, these medicines are not expected to cause different side effects or problems in older people than they do 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 using carbonic anhydrase inhibitors, it is especially important that your health care professional know if you are using any of the following:

• Amphetamines or
• Mecamylamine (e.g., Inversine) or
• Quinidine (e.g., Quinidex)—Use of carbonic anhydrase inhibitors may increase the chance of side effects

• Methenamine (e.g., Mandelamine)—Use of carbonic anhydrase inhibitors may decrease the effectiveness of methenamine

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

• Diabetes mellitus (sugar diabetes)—Use of carbonic anhydrase inhibitors may increase the patient's blood and urine sugar concentrations

• Emphysema or other chronic lung disease—Use of carbonic anhydrase inhibitors may increase the risk of acidosis (shortness of breath, troubled breathing)

• Gout or
• Low blood levels of potassium or sodium—Use of carbonic anhydrase inhibitors may make the condition worse

• Kidney disease or stones—Higher blood levels of carbonic anhydrase inhibitors may result, which may increase the chance of side effects; also, these medicines may make the condition worse

• Liver disease—Use of carbonic anhydrase inhibitors may increase the risk of electrolyte imbalance and may make the condition worse

• Underactive adrenal gland (Addison's disease)—Use of carbonic anhydrase inhibitors may increase the risk of electrolyte imbalance