The
test strips that I use are 10LG Parameter
Urine Reagent Strips which can be bought on line at a reasonable price.
These strips detect Leukocytes, Nitrite, Urobilinogen, Protein, pH, Blood, Specific Gravity, Ketone, Bilirubin, Glucose.
You can get strips that detect less.
The one that would be of interest if someone is suffering from dehydration is the Specific Gravity reading.