A swollen finger can be caused by a number of things, including injuries, infections, or even repetitive motion. If a finger is broken or infected, it is important to seek medical attention instead of trying to deal with problem yourself. If it is jammed or twisted, but not broken, and does not have an open wound, then the Rest, Ice, Compression, Elevation (RICE) method is generally the best treatment. This promotes healing and decreases pain by reducing the inflammation, improving circulation, and preventing you from accidentally damaging the swollen finger further by restricting its movement.
RICE
Rest the hand and use ice to cool the affected area. This eases the pain from the injury and reduces swelling. Do not apply the ice directly to the skin, which can reduce blood flow too much and damage the skin, potentially causing frostbite. Instead, wrap it in a towel and put it on the injury. Do this for sessions of 10 to 20 minutes, three or more times per day. It's important not to leave the ice on for more than 20 minutes at a time, since having too little blood flow in the area could cause tissue damage and slow recovery.
Next, wrap the swollen finger with an elastic bandage. Apply it tightly enough to reduce movement, but not so tightly that it cuts off circulation. If it is uncomfortably tight or causes increased pain, feelings of numbness, coolness, or tingling, loosen it. Using a non-elastic or excessively tight bandage can aggravate swelling or keep the finger from getting enough blood.
Finally, elevate your hand. This is usually only necessary for a day or two. You can also soak the finger or hand in a mixture of warm water and Epsom salts for approximately 20 to 30 minutes twice a day. If it does not improve, and is painful, warm, or tender to the touch, you should seek medical attention rule out infection, a break, or tendon damage.
Open Wounds
A little swelling is a normal part of healing for open wounds, but persistent swelling is a warning sign of infection and should be examined by a healthcare professional. You can reduce the risk of an infection by cleaning the wound thoroughly with soap and water or a disinfectant, applying antibiotic ointment, and keeping it covered with a sterile bandage.
Be sure to check the swollen finger regularly to be sure it is healing. If the swelling doesn't go down, or redness, warmth, discharge, or streaks on the finger or hand appear, seek medical help immediately. Open wounds caused by rusty objects, human or animal bites, or deep punctures are especially at risk for infection, and should receive immediate medical attention — do not wait until symptoms have already appeared to see a healthcare professional.
Other Causes
Swelling caused by arthritis or repetitive motion injuries often takes a long time to heal. Over-the-counter pain relievers and anti-inflammatory medications can provide some relief. Otherwise, resting the hand may be the best course of action. Try not to spend all day typing at the computer or continually performing other repetitive tasks with your hands or fingers without taking breaks. If you have continuously swollen fingers, then you should seek medical attention, as this could be a sign of conditions like edema, cellulitis, lupus, or gout.