Symptoms
Breakthrough pain is acute and transient pain that occurs against a background of continuous pain management. It is an acute exacerbation that is most common in chronic disease and especially in cancer. The pain is usually sudden, acute, and intense.
Causes
The exact causes are not always known. Breakthrough pain may occur as a result of a trigger, such as physical activity or coughing, or for no apparent reason. They are also observed at the end of the dosing interval of the basic therapy (end-of-dose). Breakthrough pain can be nociceptive, neuropathic, or mixed in nature.
- Known or unknown trigger.
- Spontaneous/idiopathic
- End-of-dose
Diagnosis
Breakthrough pain is often self-assessed by the patient and treated based on the physician’s instructions. A pain diary, visual analog scale, and pain questionnaire can be used as tools.
Nonpharmacologic treatment
Possible nonpharmacologic therapeutic measures are presented under the acute pain article.
Drug treatment
Fast-acting, short-acting, and flexible-dose analgesics are used to treat breakthrough pain and are administered in addition to basic pain therapy. Opioids such as morphine, oxycodone, or fentanyl are often used. If breakthrough pain is too frequent, the basic therapy (long-acting or sustained-release opioids) must be evaluated and adjusted. Different modes of application and dosage forms are used, which allow a rapid onset of action:
- Peroral: administration by mouth, absorption via the digestive tract into the bloodstream (e.g., morphine, oxycodone).
- Administration via oral mucosa: Buccal tablets, lozenges, sublingual tablets, soluble film (e.g., fentanyl).
- Intravenous: administration of an injection into a vein, usually in a hospital setting (e.g., morphine)
- Nasal: administration through the nasal mucosa into the bloodstream (eg, fentanyl).
- Inhalational: inhalation, absorption through the bronchial mucosa (eg, fentanyl).
- Patient-controlled pain therapy (e.g., morphine).
Nonopioid analgesics such as NSAIDs and acetaminophen may also be appropriate for the treatment of breakthrough pain in some circumstances.
