Help! My kitten's neck suddenly swelled up. What's happening?

This does not look like an allergic reaction which could come from a systemic medication. This lump/growth should be ideally examined by your veterinarian to have a definitive diagnosis. Your vet will examine it and possibly perform with an FNA (fine needle aspiration) or a biopsy. Differentials would include skin cyst, an insect bite, the result of a trauma, infections or benign or malignant type of tumors (very unlikely given the age). 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. If this answer was helpful please let us know, this will be used to improve our service!

I am sorry to hear about your kitten! I would recommend bringing her in for an exam at your vet. If the swelling is progressing tonight or she develops any difficulty breathing I would get her to the emergency vet. We could have swelling do to an allergic reaction from an insect bite or exposure to any other substance/plant (most of the time we don't see a mark/know the cause) but I would also want to check for things like an abscess or infected tooth causing swelling. It sounds like he may also have a mild upper respiratory infection (like us having a cold) that he has passed to the other cats. You can read more about this at https://www.petcoach.co/article/sneezing-and-feline-upper-respiratory-disease/

Hi there and thank you for using PetCoach to address your concern. This may be an acute allergic reaction and should be addressed by a veterinarian immediately so that Bibo's airway does not become occluded. If you are unable to get Bibo to a veterinarian, please have a read of the article below. I hope this helps and that Bibo gets better soon! Please let me know if you have any other questions or concerns and I would be more than happy to help you further. ( https://www.petcoach.co/canigive/cat/benadryl/ )

Facial swelling can be caused by an allergic reaction to something such as an insect sting or spider bite, an abscess from an injury, or even an abscessed tooth (unlikely in such a young cat). I would encourage you to have him evaluated by your veterinarian as soon as possible. Depending on what the diagnosis is will determine what medications are recommended. Best of luck and I hope he improves soon. Thank you for using Pet Coach.

She is a cutie! This could be from an insect/spider bite that has cause a local infection/abscess which is why is has started to swell. This could potentially be a cancerous mass that has caused an inflammatory reaction as well. Since it has recently become swollen, I would strongly recommend for your vet to take a look at it. Your vet will be able to aspirate the mass or swelling if needed. They can even take X-rays if needed if they are concerned about sinus or honey involvement. They will also be able to start her on some antibiotics and an anti-inflammatory if needed. I hope this helps!

This is an emergency. Your kitty could have a severe allergic reaction, or a snake bite or serious injury (maybe because of a collision with a car). He needs to be seen by a veterinarian right away. Please take him to a PetEr right now as this sounds life-threatening.

Thanks for using Petco Pet Education Center, formerly Petcoach! You could try to keep it clean but aside from that, I am afraid that he will need veterinary care. Puncture or bite wounds can get infected rather quickly and result in a fever which may be why he is not eating. They can form abscesses that require local treatment and antibiotics. You could perhaps consider taking him to an emergency veterinarian who is open over the weekend. Good luck and have a great day!