Control of cancer pain with analgesics acting in the central nervous system

Systemic administration of opioids is one of the traditional, but by no means optimized therapeutic procedures in cancer pain. Besides the underlying pathophysiology, appropriate treatment has to take into account the psychodynamics and behavior of the patient as well as his life expectancy. In view of this, therapy with centrally acting analgesics can be considered after administration of analgesics with peripheral action first and then of psychoactive agents. Nefopam is a centrally (but not spinally) acting analgesic with a novel activity profile. Its advantages and disadvantages in the treatment of carcinoma pain are outlined. The opiate agonist-antagonist principle has the advantage of a lower dependence and tolerance potential. In addition, the preparations pentazocine, tilidine plus naloxone, and buprenorphine deviate from the morphine derivatives in various constituent effects. Their actions and side effects are outlined. The optimization of control of cancer pain is not possible without taking into account the time dimension. In 50 pain patients with advanced cancer, the following main errors were observed in previous treatment of pain syndromes: (1) too early parenteral administration in the course of the disease; (2) underdosage; (3) application intervals that were too long; and (4) use of analgesics as needed by the patient or on request and not according to a time schedule.