Driving is a key daily activity for most adults because it provides a sense of freedom, independence and efficiency. Many adults drive on a regular basis to go to work, drop their children at school or to attend to social commitments. Being able to drive is also a crucial facilitator of many pleasurable activities like going to the cinema or travelling for leisure.
Most people with advanced disease experience uncontrolled symptoms such as fatigue, pain or breathlessness, which can interfere with their daily lives. These symptoms are both uncomfortable and extremely restrictive leading to significant functional limitations, increased anxiety and depression, and social isolation. For example, people with advanced chronic obstructive pulmonary disease are frequently so restricted by breathlessness, they describe a sense of “existing rather than living”.
For patients with advanced disease, being able to drive may help to overcome the extreme limitations imposed by their symptoms. In fact, patients with advanced disease consider driving a paramount daily activity. Literature from Sweden indicates that 23% of the community-dwelling adults receiving palliative care were still driving.  An additional 16% of these patients were not driving but still had that option in mind. For many of these individuals driving was associated with a sense of individuality, independence and hope. Thus, the issue of driving for people receiving palliative care should be critically considered by palliative care clinicians and researchers alike.
However, when considering the palliative population and driving, the aspect of necessary opioid consumption cannot be left out of the discussion. Opioids are often prescribed for pain or breathlessness management in people with advanced diseases, and they are frequently the only therapy able to provide symptom relief. For some patients, taking opioids ‘frees them up’ and enables activities they were unable to do for years, such as walking their dog and climbing a flight of stairs. However, current concerns about opioid use need to be acknowledged, including the potential impact of opioids on driving ability.
Opioids are psychoactive drugs, that have the ability to impair psychomotor skills if taken in sufficiently high doses, in an unsupervised way. For this reason, people taking opioids are often advised not to drive. However, high-quality published studies are lacking and available published literature reports inconsistent findings. While some studies suggest opioid use causes high rates of dizziness, sedation and cognitive and psychomotor impairment, other studies show no significant adverse effects. 
This issue was discussed extensively in a recent systematic review that evaluated the impact of opioid use for therapeutic purposes on driving-related psychomotor skills.  Importantly, only three studies were included in this review but all reported no significant impact of therapeutic opioids in
Nevertheless, it is now widely recognised that not all opioids are the same. They have different properties and target different opioid receptors in the body, which can produce different clinical effects. For the same opioid, different formulations and doses lead to different blood concentrations. Dose initiation and up-titration is thought to produce psychomotor impairment, but, unresolved questions remain for low dose opioid use to relieve chronic breathlessness and relevance of computer-based testing of driving ability to real-world driving ability. Is taking opioids to relieve a symptom worse than driving with that same symptom, which also affects concentration?
For now, there are no definite answers to these questions. Thus, when advising a patient to drive or not to drive, advice should be based on the best available evidence and clinical judgement informed by the type of opioid, dose and formulation prescribed, but also based on the patient’s symptoms, comorbidities and pre-morbid driving abilities. Importantly, these are crucial questions for researchers looking to contribute to improving patients with advanced disease quality of life. The first randomised-controlled trial evaluating the effects of low-dose morphine on driving-related skills, in a population with advanced disease, is currently under way. 
- Widman A, Bergström S. Driving for patients in palliative care–a reality? Springerplus. 2014 Feb 10;3:79. doi: 10.1186/2193-1801-3-79. eCollection 2014.
- Mailis-Gagnon A, Lakha SF, Furlan A, Nicholson K, Yegneswaran B, Sabatowski R. Systematic review of the quality and generalizability of studies on the effects of opioids on driving and cognitive/psychomotor performance. Clinical J Pain. 2012 Jul;28(6):542-55.
- Ferreira DH, Boland JW, Phillips JL, Lam L, Currow DC. The impact of therapeutic opioid agonists on driving-related psychomotor skills assessed by a driving simulator or an on-road driving task: A systematic review. Palliat Med. 2018 Apr;32(4):786-803. doi: 10.1177/0269216317746583. Epub 2018 Jan 4.
- Currow D, Watts GJ, Johnson M, McDonald CF, Miners JO, Somogyi AA, et al. A pragmatic, phase III, multisite, double-blind, placebo-controlled, parallel-arm, dose increment randomised trial of regular, low-dose extended-release morphine for chronic breathlessness: Breathlessness, Exertion And Morphine Sulfate (BEAMS) study protocol. BMJ Open. 2017 Jul 17;7(7):e018100.
Diana Ferreira, Doctoral Candidate, Flinders University
For more evidence around pain in a palliative care context visit the CareSearch systematic review collection.