**4. Opioids, pain and substance use disorder**

Chronic pain in patients with cancer, noncancer injury related, organ failure renal insufficiency, and trauma related individuals if they are at the end of life pain and have substance use disorder (SUD), we need to consider "comfort care" as goals and assist as best as we can.

However, similar patients engaged in survivorship, SUD need to be assessed and mental health/addiction services, need to be collaborated. Some of the patients with SUD or opioid use disorder (OUD) require Mu-agonist therapy using methadone or suboxone.

#### **5. Potential future treatments for pain**

We need to consider further research to improve care for individual patient. Chronic pain is considered as an illness with suffering. Several organizations have been working and care providers need to engage in raising questions and proceeding with research investigation.

Investigations and research in relation to genetics, non-opioids like; ion channels, alpha-2-agonists, glia, and immune cells along with non-pharmacological approach physical, psychological, social, spiritual rehabilitation and research in nutrition is worthwhile.

#### **6. Conclusion**

Palliative care consists of patients with illness in the early phase and advanced end of life care. Patient's wishes, worries, goals of care, and shared decisions along with subjective symptom like pain need to be considered.

Chronic pain is an illness and remains as a subjective symptom for an individual. Biopsychosocial, spiritual, and medical approach can benefit patient, family, and community. As care providers we ought to be up to date, evidence supported approach to relieve suffering of patient and family. Animal experiments and human clinical research have given care providers knowledge, and application of pain management can be better.

Acute pain often heals within days to weeks, but when the pain persists from an injury for more than three months chronic pain is considered. Central excitatory chemicals in the central nervous system can increase pain expression. Such change allows anxiety, frustration, and mental health issues.

Interventions like interventional, psychological, physical, pharmacological and nutrition have a value to reduce the chronic pain illness, suffering and improve function in an individual.

In the future, a2–Adrenergic agonists, ion-channel modifiers, and nanotechnology using nanoparticles to transport pharmaceuticals to reduce adverse effects and improve efficiency have a value in pain management and being investigated.

Thus, consider individual patient despite common diagnosis, require self-management skills, and endure or improve symptoms using appropriate therapies.

Education of care providers, patients and families is important; avoid stigmatizing an individual with chronic pain, substance use disorder, poor quality of life and mental health issues.
