Phenolsulfonphthalein (Diagnostic)

Brand Names : phenol red, PSP

Before Having This Test

In deciding to use a diagnostic test, any risks of the test must be weighed against the good it will do. This is a decision you and your doctor will make. Also, test results may be affected by other things. For phenolsulfonphthalein, the following should be considered:

Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to phenolsulfonphthalein. Also tell your doctor if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy - Studies have not been done in either humans or animals.

Breast-feeding - It is not known whether phenolsulfonphthalein passes into the breast milk. This medicine has not been reported to cause problems in nursing babies.

Children - Although there is no specific information comparing use of phenolsulfonphthalein in children with use in other age groups, phenolsulfonphthalein is not expected to cause different side effects or problems in children than it does 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 phenolsulfonphthalein 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 phenolsulfonphthalein, it is especially important that your health care professional know if you are taking any of the following:

• Aspirin or other salicylates or
• Atropine or
• Diuretics (water pills) or
• Penicillins or
• Probenecid (e.g., Benemid) or
• Sulfinpyrazone (e.g., Anturane) or
• Sulfonamides (sulfa medicine) - Use of any of these medicines at the same time as phenolsulfonphthalein may affect the test results

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

• Gout or
• Liver disease or
• Multiple myeloma (a kind of cancer) - These conditions may affect how fast the body gets rid of the phenolsulfonphthalein

• Heart or blood vessel disease or
• Kidney disease (severe) - Patients with these conditions are at greater risk of becoming ill because of the large amount of liquids that must be taken for this test

Preparation for This Test

Your doctor will ask you to drink a certain amount of water a little while before this test is done. Follow your doctor's instructions carefully . Otherwise, this test may not work and may have to be done again.