Tendonitis is a condition in which the tendons that connect the muscles to the bones become inflamed and sore. This is typically an "over use" condition that can be caused be repetitive actions - for example, tendonitis of the wrist is very common in those who sit and type at a computer all day long.
There is absolutely no role for diet in the treatment of tendonitis. Furthermore, alcohol should never be used to treat pain or other physical symptoms, because it is potentially damaging for the body and can also lead to dependence or alcohol abuse.
Rather, if you have tendonitis, then you should talk to your primary care doctor
about the types of treatments that are available. In the first place resting the involved body part is critical to recovery. Sometimes bracing or splinting the area can help speed healing. Furthermore, there are a number of excellent anti inflammatory medications that can help reduce the pain, and your doctor can tell you which one might be right for you. In some cases, physical therapy or stretching exercises might also be needed.
Start setting up an appointment with your primary care doctor today. They should be able to help you start getting better.