Good morning, Maxine. Thanks for your reply.
Henrietta looks to be a syrian hamster and she's very lucky you found her. It has to make you wonder why she was out on her own as this type of hamster is not native to the USA.
You've chosen a good choice for bedding as it's very low risk for irritation and allergens. Some beddings can be toxic to pocket pets like Henrietta.
Here are some additional ideas for food, if you wish to supplement in the future: http://www.hammysworld.com/index.php?p=food
The falling over, your main concern, is often due to an inner ear affliction called Vestibular Disease. With supportive care, this often resolves on it's own (sometimes it's due to an ear infection or foreign body). There's more information available here: http://www.hammysworld.com/index.php?p=tilt You'll notice this link also mentions a head tilt, which is not always present, but we often do see falling over to one side or the other with the loss of balance. Many pets often experience a lack of appetite, as well, due to the nausea that can accompany this affliction. To us, it feels like the world is spinning and we cannot find which way is up. The same is said about pets with Vestibular Disease. Many of them benefit from being handfed small bits, which might explain why Henrietta is willing to eat treats but hasn't been interested in her hay or biscuits.
Another concern, which is entirely aside from vestibular disease, is that she may have suffered a head injury prior to you finding her. In fact, it's like that due to one of these two problems, she was easily exposed in her environment so that you could find her and pick her up. By nature, even domestic animals have the desire to hide to avoid becoming prey. Something obviously kept her from being able to do this very well (and she's lucky she was found by you and not picked off by a cat, a owl, etc).
I do not have experience with the Oasis drops, but they do include an antibiotic. I am much more familiar with the use of veterinary antibiotics to treat this. That being said, her hind end looks very clean, not irritated and unlike many cases of wet tail that I've experienced. I doubt you're doing any harm by giving the Oasis. What I do see, however, is some urinary saturation of the fur, which is entirely normal. Wet tail is usually noted by a few watery diarrhea which scalds the back end of the hamster and, if not treated quickly, can result in death. That said, due to the fact that you've stated that she is having normal stool, I very seriously doubt she has wet tail (which is a great thing as stress often causes diarrhea and being loose in the wild is definitely stressful!)
If she were my hamster, I would locate a veterinarian who was comfortable treating pocket pets. A check of both ears will be needed and a physical exam. Your vet may also wish to run a fecal exam to check for any parasites which might lead to a neurological disorder and so forth. The treatment is often simple and time usually resolves the symptoms of vestibular disease. If you elect to wait and watch, be mindful of progressive symptoms and be prepared to take her in if she goes downhill. In the meanwhile, try feeding her small bits of food and take a look at the link above for other items she may eat readily if she's not willing to eat her commercial diet. You may also wish to offer her water via a dropper to see if she will take it. If her refusal to drink continues, she may also need SQ fluids during her veterinary appointment.
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