The treatment of breakthrough pain.

OBJECTIVE: To review strategies for treating patients with breakthrough pain (BTP).
DESIGN: This review is based on expert consensus recommendations for treating BTP and is supplemented by recent clinical studies and the author's clinical experience.
RESULTS: Breakthrough pain is severe or excruciating pain of rapid onset that can disable or even immobilize the patient. Patients with BTP should be assessed after baseline persistent pain has been stabilized with around-the-clock (ATC) analgesics. Clues about the cause and pattern of BTP may be identified from a patient history, preferably including a pain diary. Effective treatment can greatly improve the patient's quality of life and should be tailored for each patient, taking into consideration the cause and type of the BTP episodes. Short-acting opioid analgesics are the primary treatment. The absorption characteristics, onset of action, and duration of effect vary among the available opioid compounds based on their lipophilicity. The dose and/or dosing frequency of the ATC analgesic should be adjusted for patients with end-of-dose BTP. Short-acting oral opioids are useful when given preemptively in patients with predictable incident BTP, while rapid-onset transmucosal lipophilic opioids are most effective for patients with unpredictable incident or idiopathic BTP. Regardless of the subtype of BTP, nonpharmacologic strategies are often helpful in alleviating pain and anxiety and should be used to supplement pharmacologic intervention for BTP.
CONCLUSION: Breakthrough pain can often be successfully treated by tailoring opioid therapy based on the subtype of BTP. These characteristics of BTP will determine the most appropriate opioid compound (i.e., hydrophilic vs lipophilic) and most effective mode of drug delivery.