‘WHO has developed a three-step "ladder" for cancer pain relief.
If pain occurs, there should be prompt oral administration of drugs in the following order: nonopioids (aspirin and paracetamol); then, as necessary, mild opioids (codeine); then strong opioids such as morphine, until the patient is free of pain. To calm fears and anxiety, additional drugs – “adjuvants” – should be used. To maintain freedom from pain, drugs should be given “by the clock”, that is every 3-6 hours, rather than “on demand” This three-step approach of administering the right drug in the right dose at the right time is inexpensive and 80-90% effective. Surgical intervention on appropriate nerves may provide further pain relief if drugs are not wholly effective.’
http://www.who.int/cancer/palliative/painladder/en/


‘Basic rules of medical pain therapy according to the WHO pain relief ladder, the regular intake of medicines and a pain survey with individual dose adjustment should be observed.’
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