Palliative care physicians proposed to add topical analgesics into the WHO stepladder in the treatment of cancer-related pain to have more treatment possibilities without side effects. The WHO stepladder for pain consists of 3 steps: 

  1. Non-opioid with or without adjuvants
  2. Adding weak opioid
  3. Adding strong opioid

The authors propose to add topical analgesics depending on the type of pain. In the presence of neuropathic pain characterized by hyperalgesia, allodynia and radiating pain, they propose to use a topical analgesic containing ketamine with or without clonidine, gabapentin, methadone, bupivacaine.

Topical Innovations has gathered quite some supportive information related to this topic which points in the same direction. By targeting the skin a number of pain states are treatable by topicals which were previously considered non-treatable.

Reference

Winegarden JA, Daniel CB, Ylisabyth BS. Topical Ketamine with Other Adjuvants: Underutilized for Refractory Cancer Pain? A Case Series and Suggested Revision of the World Health Organization Stepladder for Cancer Pain. J Palliat Med. 2020 Sep;23(9):1167-1171.