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"Why is my thumb swollen?"

ZocdocAnswersWhy is my thumb swollen?


My left thumb swelled up and is red for the last two days. I can't see a bite mark or anything. What's going on? Could something have bitten me and I don't know?


There could be a few different things going on. A skin infection is certainly a possibility. Often these infections start with small cuts that you can't even see (or bites). They can also occur through small infections at the nail fold, which can occur if you have frequent manicures or if you bite your nails. If you notice that the skin is red and warm, then these are signs that you may have this type of infection. If so, you should see your primary care doctor immediately. If the infection is severe, you may need oral antibiotics to bring the infection under control. If the infection is limited just to the nail fold, this is called a paronychia and it can often be managed just with warm soaks and topical antibiotic creams. Your doctor will be able to help your sort this out. Another possibility, if this is not a skin infection, is that you could have a joint inflammation. This would be more like if the redness and swelling is centered around one of the joints in the finger rather than in the overall skin of the finger. Regardless, the first step is to go see your doctor!

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