My cat's urine specific gravity is low. Is increased water the cause?

That would depend on the hydration status of Woody and the blood values BUN and CREA (that are essentially elevated in kidney failure). If BUN and UREA are normal and USG is 1.018 means that kidneys are working absolutely normally. Hope that makes sense, if not please post another question on the forum or request a consultation with us.

Steroids interfere with antiduretic hormone which normally is responsible for resorbing water in the kidneys. Thus more water is lost in the urine making it much more dilute. This is likely why you are getting low readings for usg. If you are still concerned you could have your vet run an SDMA check on blood for early signs of kidney problems

In cats with urinary irritation, wet food is preferable to help reduce urine concentration and flush out the bladder. I strongly recommend a urine exam in order to determine exactly what is going on and to guide the most appropriate treatment (infection/inflammation etc). A sample can be collected using special urine collection litter which does not absorb urine. Petco provide a home kit for detecting UTI which can help to monitor such conditions

Stress related (idiopathic type of inflammation) infection and presence of crystals are the most common causes of it. Struvite crystals are very common and usually comes from alkaline urine. Specific diets can be given to acidify urine like s/d by Hill's. I would recommend to have a look at this link to have more informations about FLUTD (feline-lower-urinary-tract-disease): https://www2.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/feline-lower-urinary-tract-disease. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. Please find the time to give us a feedback about the consultation as that will be used to improve our service.

Unfortunately together with the hyperthyroidism (which i guess he is on treatment with methimazole) Beau is affected by mild kidney failure. USG (urine specific gravity) is usually used to assess the ability of kidneys to concentrate urine when BUN (urea and possibly crea) are elevated. In this case Beau has an elevated BUN but is not able to concentrate urine efficiently. This is a quite common condition of old cats on treatment with hyperthyroidism.

If her blood work and specific gravity of her urine sample are normal then I would.l not worry about an supplements at this time. You can continue to monitor her urine for any changes as this can indicate kidney disease before the blood work can.

The concentration of the urine depends on a number of factors, including hydration, and has to be looked at in conjunction with the overall clinical picture. I wouldn't put too much stock in that one value right now. It sounds like you are doing everything right to help Duck feel better. Here is a link on how to pill a cat http://www.hsi.org/assets/pdfs/eng_ht_pill_cat.pdf. If it is too difficult to pill Duck, ask your vet for a liquid option if possible. Cystitis can sometimes start due to stress. There are many things that you can do to help alleviate stress and help Duck feel better. Cats need at least one litterbox per cat plus one extra to help reduce stress associated with the litterbox. They should be placed in separate rooms, away from the food and water bowls, must be scooped at least daily (preferably multiple times a day)and washed out at least weekly with a mild soap, followed by thorough rinsing. Cats need a lot of space to explore, but keeping them indoors is much safer than letting them outside, due to the risk of injury from cars, wildlife, other animals, etc. The key is providing space (particularly vertical space for climbing, such as cat trees, ledges, and the like) inside the home. Visit http://www.veterinarypartner.com/Content.plx?P=T&C=33&S=2 and https://indoorpet.osu.edu// for tips on stress reduction. Also look into Feliway, a synthetic pheromone that is available in a diffuser and spray form that promotes calm feelings in cats http://www.feliway.com.