Hello and welcome. My name is ***** ***** I'm a biologist with over 40 years of experience raising and showing rabbits. I'm sorry to hear of this problem.
Your rabbit is definitely exhibiting signs of severe pain. The hunching up, the grinding teeth, and restlessness all point to that. We have no way of determining the cause of the pain. However, the symptom of not eating makes this an emergency situation. Whenever a rabbit won't eat, it is considered an emergency. After just a couple of hours, the digestive system can shut down. This is called gastro-intestinal stasis, and it is life-threatening. One of the most common things we hear about rabbits is "My rabbit stopped eating, and then he died."There could be gas in the stomach that cannot pass or there could be a blockage in the intestines. You need to get him to a rabbit vet as soon as possible. You can read more about stasis here:
Until you can get to a vet, you can give your rabbit a stomach massage. Most rabbits actually enjoy this and it can get things moving again sometimes. Place him on his back on your lap and gently massage. If you can get some children's liquid simethicone (sold in pharmacies), give him some from a syringe. You can't overdose it, and it helps break up any gas bubbles in the stomach. If you absolutely cannot get into a vet, you need to get some food into his stomach. Crush some pellets to a fine powder. Mix with enough water to make a slurry. Then use a syringe to put a couple of drops at a time in the side of his mouth (not straight down his throat). These steps are only first aid, not a cure.
If you have more questions about this, just let me know by clicking on REPLY. I hope your rabbit will reach a full recovery.
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