From the Guidelines
Morphine is the preferred liquid opioid for managing dyspnea (breathlessness) in palliative care settings, with a recommended starting dose of 10 mg per day, given to provide a steady state according to preparation (2.5 mg immediate release regularly four times daily; 5 mg modified release twice daily or 10 mg modified release once daily) 1. The use of opioids for dyspnea is supported by several studies, including a review of palliative care for people living with heart failure, which found that morphine should be started at 10 mg per day, with dose increases not occurring for at least one week if the response is inadequate 1. Some key points to consider when using liquid opioids for dyspnea include:
- The mechanism of the antidyspnoeic effect of opioids seems complex and is mediated via opioid receptors of the cardio-respiratory system as well as different areas in the central nervous system 1
- Opioids reduce the unpleasantness of dyspnea and can be used in opioid-naive as well as in opioid-tolerant patients without causing relevant breath depression or impaired oxygenation or increase in CO2 concentration 1
- Patients receiving opioids for breathlessness experience the well-known opioid-related unwanted side effects, e.g. initial nausea and persistent constipation, and prophylactic laxatives should be prescribed concurrently 1
- Regular reassessment is essential to balance symptom relief against side effects, with dose adjustments made accordingly, and for severe dyspnea requiring rapid relief, subcutaneous or intravenous administration may be more appropriate than oral liquid formulations 1
- Other opioids, such as oxycodone, may also be used, but there is limited evidence to support their use, and morphine should be avoided in patients with severe renal insufficiency 1
From the Research
Role of Liquid Opioid in Treating Dyspnea
- The use of liquid opioids, such as morphine, for the treatment of dyspnea has been investigated in various studies 2, 3, 4, 5, 6.
- These studies suggest that low-dose opioids may be effective in reducing dyspnea in patients with acute respiratory failure, terminally ill patients, and those with chronic obstructive pulmonary disease (COPD) 2, 3, 4, 5.
- The primary objective of these studies is to determine the efficacy of opioids in reducing dyspnea, with some studies also investigating the safety and tolerability of opioid administration 2, 3, 4, 5.
Administration and Dosage
- The administration of opioids for dyspnea can be via various routes, including intravenous, subcutaneous, oral, and nebulization 3, 4, 5.
- The dosage of opioids used in these studies varies, with some studies using low-dose morphine or fentanyl, while others use higher doses or combination therapy 3, 4, 5.
- The optimal dosage and administration route for opioid treatment of dyspnea is not yet established and requires further research 6.
Efficacy and Safety
- The studies suggest that opioids can provide subjective relief of dyspnea in patients with acute respiratory failure, terminally ill patients, and those with COPD 2, 3, 4, 5.
- However, the quality of evidence is limited, and further research is needed to establish the efficacy and safety of opioid treatment for dyspnea 6.
- Common adverse effects of opioid administration include sedation, drowsiness, and respiratory depression, which can be managed with careful dosing and monitoring 3, 4, 5.