Swollen fingers with no joint pain can be caused by fluid retention, infection, inflammation or trauma, Healthgrades explains. During pregnancy or menstruation, hormonal changes cause the body to retain fluids, causing all the fingers as well as other parts of the body to bloat.
Insect bites, rashes and hives also cause fingers to swell without the accompaniment of joint pain, states Healthline. These swellings can stay in a single area or spread depending on the impetus of the swelling. If the swelling is not confined to just the finger but also affects other parts of the body, it can be a sign of a more serious problem such as organ failure, an allergic reaction or a venomous insect bite. If the swelling is caused by an insect bite or trauma to the appendage, then pain, itching and vomiting can result as well. Sometimes people with cancer or diabetes experience occasional swelling in either their fingers or toes.
A single finger swelling can be indicative of an infection, states Healthgrades. If the swelling doesn't go away but becomes hot, red and inflamed, the person needs to see a medical professional right away to prevent any serious results or side effects from the infection.