The present invention relates to the use of selective 
aquaporin inhibitors, e.g., of 
aquaporin-4 or 
aquaporin-2, e.g., certain phenylbenzamide compounds, for the prophylaxis, treatment and control of aquaporin-mediated conditions, e.g., diseases of water imbalance, for example 
edema (particularly 
edema of the brain and 
spinal cord, e.g., following trauma or 
ischemic stroke, as well as the 
edema associated with 
glioma, 
meningitis, acute mountain sickness, epileptic seizures, infections, metabolic disorders, hypoxia, water intoxication, hepatic failure, 
hepatic encephalopathy, diabetic ketoacidosis, 
abscess, 
eclampsia, Creutzfeldt-Jakob 
disease, and lupus cerebritis, as well as edema consequent to microgravity and / or 
radiation exposure, as well as edema consequent to invasive 
central nervous system procedures, e.g., 
neurosurgery, endovascular clot removal, spinal tap, 
aneurysm repair, or 
deep brain stimulation, as well as 
retinal edema), as well as 
hyponatremia and excess fluid retention, and diseases such as 
epilepsy, 
retinal ischemia and other diseases of the eye associated with abnormalities in 
intraocular pressure and / or tissue hydration, 
myocardial ischemia, 
myocardial ischemia / 
reperfusion injury, 
myocardial infarction, myocardial hypoxia, congestive 
heart failure, 
sepsis, and 
neuromyelitis optica, as well as migraines, as well as to novel assays for identifying aquaporin inhibitors.