We Are Dealing With An Inflamed Elbow. It Is Swollen

We are dealing with an inflamed elbow. It is swollen and red, and warm to the touch. There is no sign of a wound or bite. We tried epsom salts, and warm water. He took a couple Ibuprofen. Now he is feeling exhausted and laid down to try and rest. It is on the back of the elbow, and the redness and swelling is about 7 inches long.