Pain Management Part 2 Use of Adjuvants John Mulder, MD, FAAHPM Vice President of Medical Services Faith Hospice Director, GR MEP Palliative Medicine Fellowship Program

Coanalgesic Drugs (Adjuvant Therapy) Definition: Drugs which enhance analgesic efficacy of opioids, treat concurrent symptoms that exacerbate pain, or produce independent analgesia for specific types of pain. Early use optimizes comfort and function by preventing or reducing side effects of higher doses of opioids

Coanalgesic Drugs (Adjuvant Therapy) Most amenable cancer pain syndromes Bone metastases Neuropathic pain Visceral distention Most commonly used coanalgesic drugs NSAIDs Corticosteroids Antidepressants Anticonvulsants

Bone Metastases - Adjuvants NSAIDs Steroids Decadron 4mg BID, titrate Bisphosphonates Zometa, Aredia Radioisotopes

Neuropatic Pain – Adjuvants Tricyclic antidepressants Anticonvulsants Steroids

NSAIDs Antidepressants TCA - Elavil, gold standard; desipramine SSRI - Paxil only one shown effective thus far; Serzone, Effexor promising Psychostimulants - dietary caffeine, Ritalin, amphetamines Alternative/Adjuvant Medications

Neuroleptics Benzodiazapines (watch for sedation) Anticonvulsants - especially for neurogenic pain (Neurontin) Baclofen Steroids - high dose, short term/low-dose, long term for bone or neurogenic pain Antihistamines Alternative/Adjuvant Medications

Steroids - high dose, short term/low-dose, long term Antihistamines (Benedryl, Vistaril) Alpha-2-adrenergic stimulants (Clonidine) Cannabanoids Alternative/Adjuvant Medications

Capsaicin Colchicine Thalidomide Ketamine Lidocaine Dextromethorphan - (no guaifenesin or alcohol) - 30 mg BID - 1 g/d ( mg/d usual )

Narcotic Resistant Pains Headaches Muscle Spasm Tenesmoid (Bowel / Bladder) Incident to movement Decubitus Deafferentation

Deafferention Pain Type I Complex Regional Pain Syndrome A syndrome characterized by severe burning pain in an extremity accompanied by sudomotor, vasomotor, and trophic changes in bone without an associated specific nerve injury.... Complex Regional Pain Syndromes Conditions characterized by pain involving an extremity or other body region, HYPERESTHESIA, and localized autonomic dysfunction following injury to soft tissue or nerve. The pain... Reflex Sympathetic Dystrophy Syndrome A syndrome characterized by severe burning pain in an extremity accompanied by sudomotor, vasomotor, and trophic changes in bone without an associated specific nerve injury....

OMM Acupuncture Acupressure Massage Therapy Music Therapy Hypnosis Relaxation Non-pharmacologic Interventions

Unwarranted / Exaggerated Fears Respiratory Depression Addiction Rapid Tolerance Regulatory Reprisal

Opiate Side Effects: Constipation –Most common side effect - expected –Mediated spinally and in GI tract –Decreased peristalsis & decreased intestinal secretions –Tolerance does not readily occur –Treat with peristaltic agent and softeners - prophylactically

Opiate Side Effects: Pruritis –Caused by opioid induced histamine release –Tolerance generally develops quickly –Difficult cases may require a change in opioid –Usually treated with transient use of antihistamines

Opiate Side Effects: Somnolence / Sedation –Common, but tolerance typically develops within a few days –Sedation varies with opioid and dosing schedule –Additive effects with other cerebral depressants –Decrease or discontinue other cerebral depressants –Concurrent use of Dextroamphetamine or Methylphenidate is helpful, but tachyphylaxis is common

Opiate Side Effects: Hallucinations / Confusion –Less common, but may occur especially in older patients –Often an indication of excess dosing –Try dose reduction or different opioid

Opiate Side Effects: Nausea / Vomiting –Occurs in 50 – 65% of patients on oral morphine –Varies with drug and route –Usually easy to control, occasionally severe and difficult to control

Opiate Side Effects: Urinary Retention –Opioids increase smooth muscle tone (sphincter) –May also cause bladder spasms –Try changing opioids or insertion of catheter

Opiate Side Effects: Myoclonus –Can occur with all opioids –Typically due to high doses and/or dehydration –Long half-life metabolites are typically implicated –Reduce dose, change opioids, change routes and/or hydrate patient

Opiate Side Effects: Respiratory Depression –Cause of death in opioid overdose –Tolerance develops rapidly –Rarely a concern with appropriate dose escalations –If accidental overdose occurs in a patient chronically receiving opioids, dilute Naloxone 1:10 and titrate very carefully to reverse respiratory depression without precipitating withdrawal or reversing analgesia