My boy, Chao-Guay, used to drink 4-6 oz of water a day. And after neutering, he drank like crazy, almost 20 oz a day. I called the vet and she said it was not normal and I should take him to run the tests. Chao-Guay ate, pooped, and acted normal. So, my husband and I decided to let him be because we didn’t want to stress him any more. (I didn’t mention besides neutering, the vet ran so many tests earlier on him due to asymmetrical face.) I kept monitoring him and eventually his drinking came back to normal. I would say it took over a month. I didn’t know because it was the hot weather (july-August in MN) or he had too much drug in his system from the surgery and tried to get rip off it. (He totally hallucinated on the night of the surgery and didn’t do well at all the whole night). But anyway, I think it depends on a situation. For Chao-Guay, I think it due to surgery. So, is there anything you can think of that may trigger his excessive drinking?

He could have a UTI or EC. Bombur’s first symptoms of EC were drinking and peeing excessively. It’s definitely worth a visit to at least treat for a UTI.

Besides going in for a vet visit, it would be wise to limit the amount of spinach you are giving your rabbit. Spinach is high in oxalic acid and should not be given daily. Over time, consumption of foods high in oxalic acid can cause problems, including damage to the kidneys.

There are a lot of good greens to choose from for your rabbit. Here is one list:

https://rabbit.org/suggested-vegetables-and-fruits-for-a-rabbit-diet/

If he eats more hay he will drink more. Normal water consumption for a rabbit is around 100 ml water per kilo body weight. But if you give fresh veg and wet greens the rabbit will get a lot of water from that and drink only a little.

Drinking a lot of water is an observandum in all animals, incl humans. It can signify lots of things, ranging in severity from very minor to quite grave. Try to make an estimate of the amount of water he gets per day so you can tell your vet. It’s odd his pee is smelling more though, if an animal or human drinks a lot the urine tends to become very dilute and almost scent free.

Drinking a lot more water was the first sign of my bunny’s kidney failure, they drink more to flush the toxins out of the kidneys. They did a urine and blood test to determine how bad he was. That was back in July and he’s still hanging in there.

I agree with tobyluv about the spinach, I think the main veggie bunnies are supposed to have is romaine lettuce. I give mine romaine, parsley, cilantro and a baby carrot every day. I used to feed mine spinach but it calcified their urine.

My bunny was drinking an enormous amount when we got him, which we found out was because he was in kidney failure. But his pee was very dilute and did not smell at all. I had him treated for EC and his symptoms improved and now he drinks half as much as long as I keep him on a kidney failure diet.

In your case my first suspicion would be a UTI. If he is drinking a lot his pee should be less smelly.

Are there any other symptoms apart from the excessive peeing? Did he lose weight or is he more lethargic etc?

My bunny Kurotta was eating and drinking more excessively back in May and the vet put him on Fenbendazole (a treatment for EC) just in case. He improved shortly after. That was coupled with other symptoms like hind leg weakness and weight loss though. You may want to observe further and see if there are any other signs.