You can give him baby gas drops (simethicone). You give 0,5 – 1 ml of normal strength gas drops, once every hour for 3 hours, then 0,5 ml every 2 or 3 hours until you feel he’s alright. Treatment can then be repeated the next day if needed.Gas drops are available at Walmart etc in the USA or Tesco in the UK or any pharmacy. It’s bunny safe and frequently used against gas in bunnies.
How does his poop look and how is his appetite? Since he’s recently lost his friend, he might get tummy trouble due to that – it’s stressful for a bun to loose a friend, as I know you know.
Is his activity-level normal (moving around)? Moving around can also help with getting gas out. Bunnies often get pain when they have gas, so you want to get it out, I e you want him to fart, literally. (You probably won’t be able to hear him fart, but you might smell it, a cecal-like smell.)
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