Pain management : challenges

For chronic pain

Chronic pain is an individualised experience with multifactorial aetiology. Chronic pain is not simply a chronological extension of acute pain and requires different diagnostic approaches and management strategies. Chronic pain is typically associated with and exaggerated by coexisting conditions such as anxiety, depression, catastrophising, and disability; and the effectiveness of medications used for acute pain can diminish over time because of tolerance (for example, with opioids) or increased side effects.6

Chronic pain is a unique challenge to health professionals that demands a sensible and pragmatic management strategy.6

Recognising limitations of pain medications

All commonly used analgesics have important limitations when used for chronic pain.6
For example,

  • Prolonged use of paracetamol (acetaminophen) can cause changes in liver function that are exacerbated by concurrent alcohol consumption6
  • Prolonged use of non-steroidal anti-inflammatories are associated with potentially serious renal, gastrointestinal, and cardiovascular side effects.1 Their use May not have clinically significant improvement in certain types of chronic pain such as low-back pain and osteoarthritis.7
  • Opiates are commonly used for the management of acute pain but evidence of their efficacy and risk benefit profile in treating chronic pain is not as robust. Use of opiate medications to treat pain is associated with significant side-effects including constipation, respiratory depression, impaired cognitive ability, immune suppression, and opioid-related endocrinopathies.7 Also responsible for long-term treatment with opioids can also lead to tolerance, hyperalgesia, addiction, and misuse.6

Neuropathic pain

At least 45% of patients with neuropathic pain are treated with two or more drugs. 8 Many patients do not achieve satisfactory pain relief even with evidence-based treatment, or do not tolerate effective doses because of adverse effects. 9
Antiepileptic drugs (e.g., gabapentin, pregabalin): 10

  • Current treatment drugs such as gabapentin, pregabalin and duloxetine etc. have annoying side effects such as drowsiness, dizziness, blurred vision, somnolence, peripheral edema etc.
  • Using these drugs in the long term causes desensitization of neuron receptors. Thus, the dose of these drugs has to be increased to elicit the desired response and that leads to more number of side effects.
  • Require dose adjustment in renal impairment.

Tricyclic antidepressants (TCAs): troublesome side effects: postural hypotension, dry mouth, and sedation in the elderly population which leads to an increased risk for falls and fractures.6
The main limitations of the currently available treatment include incomplete pain relief and medication side-effect profiles.8
The current treatment paradigms have some gaps and require some new arsenal to fight against neuropathic pain. Needed at this critical juncture is a solution which corroborates to the core of neuropathic pain with no or minimal side effects.10

References

  1. Mao J. Challenges of managing chronic pain. BMJ. 2017 Feb 17;356:j741. doi: 10.1136/bmj.j741
  2. Artukoglu BB, Beyer C, Zuloff-Shani A, Brener E, Bloch MH. Efficacy of Palmitoylethanolamide for Pain: A Meta-Analysis.
    Pain Physician. 2017 Jul;20(5):353-362
  3. Cruccu G, Truini A. A review of Neuropathic Pain: From Guidelines to Clinical Practice.
    Pain Ther. 2017 Dec;6(Suppl 1):35-42. doi: 10.1007/s40122-017-0087-0
  4. Brooks KG. Treatments for neuropathic pain. Clinical Pharmacist. 2017;9(12):online. DOI: 10.1211/CP.2017.20203641
  5. Chaurasia ID, Vinayak K, Tiwari S, Malpani P, Behram S, Koshariya M. Therapeutic benefit of palmitoylethanolamide in the management of neuropathic pain. Romanian Neurosurgery. 2018;XXXII 4:654-61.