Why is my hamster biting its fur out? What are the possible causes?

Thanks for reaching out about Bobo and including photos, although difficult to determine a lesion by the pictures. Do you have mosquito problems? External parasites such as mites or fleas are possible, as are bacterial skin infections. Try cleaning the area with a mild soap. If the lesion or hair loss progresses, a veterinary visit is recommended to assess and provide a diagnostic/treatment plan. Good luck.

Thanks for reaching out about Peppermint and including photos (although they are a little out of focus). Hair loss and chewing at the skin could be an indication of a lesion (mites, bacterial, other) and being irritating and over-groomed. Most hamsters are nocturnal, so active at night. If having a skin problem could be more secretive. A veterinary visit is recommended to assess and provide a diagnostic treatment plan. Good luck.

Hello! Salem may very well have mites, or possibly another type of skin infection, such as bacteria or ringworm. I would recommend taking him into a vet to find out what the cause of the scabs are, because the treatment is different for every cause. They will likely recommend a skin scraping and taking a sample of his hair to investigate what the source of the problem is. I hope this helps!

I am so sorry to hear that this is happening with Ruby. Self mutilation in hamsters is often due to stress or disease, and with her age, I would be concerned that there may be an underlying disease process going on, and this could be causing her irritation or pain. I would recommend taking your hamster into a veterinarian. They can evaluate the area and see if there is an obvious underlying reason for the wound and hair loss, and they may recommend diagnostics, including evaluating the hair and scraping the skin. They then can evaluate the samples under the microscope. Depending on the results, they may recommend treatments, and if it is determined that treatment is not a good option for you and Ruby, they can also assist in humane euthanasia. I hope that gives you a place to start, and I wish you the best of luck.

Thank you for using Petco Pet Education Center, formerly Petcoach! It is a little difficult to see in the photo, but there is what appears to be a small area of scabbing and hairloss, both of which are patchy on the hip. This can be caused by a skin infection, certain cancers, fungal infections, or skin mites which are very common in hamsters. These mites live within the hair follicles rather than cage surfaces, so cleaning the cage will not get rid of any of the possible causes. Mochi should be seen by a vet who can perform some quick tests on this area of skin to determine the underlying cause and start her on the appropriate treatment. In the meantime, to keep her more comfortable, you can gently trim her nails to keep her from traumatizing herself as she scratches. I hope this helps!

That could be commonly caused by a mites infestation or a bacterial infection. A clinical examination at your local veterinarian is essential to confirm these clinical suspicions and treat appropriately. Antibiotics may be needed. 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.

This presentation could be due to a trauma or localized spot of skin infection (likely to be caused by bacteria). A check up, appropriate disinfection and possibly antibiotics (oral, topical or in a shampoo formulation) are needed to solve the problem. 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.