[Treatment and management of intractable chronic pain patients--preface and comments].

Chronic intractable pain is well known to be very difficult in management. The mechanisms of intractable chronic pain are complicated. Therefore, such a patient is often involved with multiple pain mechanisms and needs multiple drugs which have different types of analgesic actions. This new insight into pain mechanisms is important in the diagnosis and treatments of chronic intractable pain patients and the concept of balanced analgesia is widely accepted. Therefore, the evaluation of many factors which modulate the pain behavior is important. Opioids such as morphine and other analgesics are sometimes useful for the treatment of chronic intractable pain. Nerve blocks and interventional treatments are also helpful.