Level I Other Management
Pharmacologic Management
Key Points:
- A thorough medication history is critical to the development of an effective treatment plan.
- Define the goals of therapy before prescribing, and tailor medications to meet the individual goals of each patient.
- Identify and treat specific source(s) of pain, and base the initial choice of medication(s) on the severity and type of pain.
- Patients need to know that whether prescribed or non-prescribed, all drugs have risks and benefits. Watch for and manage side effects.
- For opioid therapy:
- Use caution before starting a patient on long-term opioid therapy
- Follow the 4 A's (Analgesia, Adverse drug reactions, Activity, Adherence) [R]
- The work group recommends the use of a written opioid agreement for patients anticipated to be on long-term therapy. See Appendix F in the original guideline document for an example of an opioid agreement form.
Medications are not the sole focus of treatment in managing pain. They should be used when needed to meet overall goals of therapy in conjunction with other treatment modalities: psychosocial and spiritual management, rehab and functional management, non-pharmacologic and complementary medicine, and intervention management. Pharmacotherapy may include agents to treat specific types of pain, such as neuropathic pain, or adjunctive therapies to treat other comorbidities such as depression and anxiety. Use of medications therefore should be directed not just towards pain relief, but increasing function and restoring overall quality of life.
The basic elements to include anytime opioids are used are a diagnosis, a care plan, regular visits with the physician, follow-up, and documentation. See the Federation of State Medical Boards at: http://www.fsmb.org for complete information.
General Principles for Pharmacologic Management [R]
- A thorough medication history is critical to the development of an effective treatment plan.
- Include use of over-the counter drugs and herbals and other supplements.
- Look for drug related fears and misconceptions, as they may lead to poor compliance with a therapeutic regimen. Differentiate between tolerance, physical dependence, and addiction. See "Definitions" in the original guideline document.
- Define the goals of therapy before prescribing, and tailor medications to meet the individual goals of each patient.
- Identify and treat specific source(s) of pain, and base the initial choice of medication(s) on the severity and type of pain.
- Types include neuropathic, muscular, inflammatory, and mechanical/ compressive pain. See Annotations #15-18 above.
- Give drugs an adequate therapeutic trial. When treating inflammatory or neuropathic pain, benefits may take weeks or longer to appear.
- Patients need to know that whether prescribed or non-prescribed, all drugs have risks and benefits. Watch for and manage side effects.
- Select an appropriate drug based on:
- Characteristics of the agent (onset, duration, available routes of administration, dosing intervals, side effects). The least invasive route of administration is preferred; it's generally oral.
- Patient factors (age, co-existing diseases, other medications, and response to previous treatments).
- Establish a pain management plan that may include the addition of other drugs: non-opioid, plus opioid, plus adjuvant analgesics when indicated.
- Rational poly-pharmacy may include the use of two or more drugs with complementary mechanisms of action that may provide greater pain relief with less toxicity and lower doses of each drug.
- Avoid prescribing two drugs in the same class at the same time.
- Be alert for possible interactions with other medication the patient is taking or additive side effects.
- Titrate doses to achieve optimal balance between analgesic benefit, side effects, and functional improvement.
- Some medications require gradual upward titration to achieve optimal analgesia and to minimize adverse effects.
- Optimize administration of analgesics. Generally, better pain control is obtained with regularly scheduled doses and supplemented with as-needed doses for breakthrough pain.
- Taper and discontinue drugs that don't meet treatment goals. If a drug does not produce the desired therapeutic outcome, there is no need to continue it. This practice helps to prevent expensive and potentially dangerous poly-pharmacy.
Non-Opioid Analgesics
Non-opioid analgesics to consider for use in the treatment of chronic pain include acetaminophen and NSAIDs.
Acetaminophen is an analgesic that may be used initially for the treatment of mild chronic pain or to supplement other agents in treating mild to moderate pain. It lacks anti-inflammatory effects, but is generally well tolerated at therapeutic doses. It does not damage the gastric mucosa but may have chronic renal or hepatic adverse effects [R]. Dosage should be restricted to a maximum of 4 grams per 24 hours, including acetaminophen contained in combination opioid products such as hydrocodone with acetaminophen. Acetaminophen should be used cautiously or avoided in patients with liver impairment.
NSAIDs
NSAIDs are indicated for the treatment of mild to moderate inflammatory or non-neuropathic pain. All NSAIDs inhibit the enzyme cyclooxygenase (COX) inhibiting prostaglandin synthesis. The COX-2 inhibitor celecoxib appears to have fewer gastrointestinal side effects.
However, high dose, long-term use of COX-2 agents has a higher rate of cardiovascular adverse effects. Recent reports indicate that cardiovascular adverse effects are not limited to the COX-2 agents alone [Not Assignable].
- All NSAIDs have gastrointestinal (GI) risks of gastritis and possible bleeding. Risk benefits should be weighed especially when treating elderly patients or those at higher risk for GI adverse effects. Consider using in combination with the gastroprotective agent misoprostol or a proton pump inhibitor.
- Use with caution in patients with coagulopathies or thrombocytopenia and those at risk for bleeding.
- Chronic NSAID use increases the risk of renal insufficiency, especially those with diabetes, and patients should be monitored for signs of reduced renal function.
- Ketorolac should not be used for longer than five days and therefore is not an appropriate choice of NSAID in the treatment of chronic pain.
- NSAIDs have significant opioid dose-sparing properties and in turn may reduce opioid-related side effects.
- Monitor all NSAID use including patient use of non-prescription drugs to prevent duplication of therapy and adverse effects.
Opioids
When is it appropriate to use opioids?
Prior to consideration of opioid use for the patient with chronic pain, a thorough evaluation as recommended in this document, should have been completed. If the ethical imperative to relieve pain requires opioid therapy prior to such a thorough evaluation, precede using good clinical judgement.
It is appropriate to consider opioid therapy for patients with persistent moderate to severe pain in the following circumstances:
- Clinical evidence suggests opioids are likely to be effective in neuropathic pain that is not responsive to initial therapies (tricyclic anti-depressants [TCAs] or gabapentin). Opioids are rarely beneficial in the treatment of inflammatory or mechanical/compressive pain and are not indicated for chronic use in treatment of headache (see the NGC summary of the ICSI guideline Diagnosis and Treatment of Headache).
- Opioids have an equal or better therapeutic index than alternative therapies.
- The medical risk of opioid therapy is relatively low.
- The patient is likely to be responsible in using the drug.
- Opioid therapy is considered part of the overall management for the pain syndrome.
Physicians should not feel compelled to prescribe opioids or any drug if it is against their honest judgment or if they feel uncomfortable prescribing the drug. Before prescribing an opioid, the work group recommends using the DIRE tool to determine a patient's appropriateness for long-term opioid management (see Appendix E in the original guideline document). Other opioid assessment tools include Webster's Opioid Risk Tool, the Screener and Opioid Assessment for Patients in Pain (SOAPP®), and the Current Opioid Misuse Measure (COMM™).
Patients should give informed consent before the start of opioid therapy and the consent discussion should be documented in the medical record. This discussion should include the low risk of opioid addiction in patients under a physician's care, the necessity of adherence to prescribed dosing, the potential for cognitive impairment when taking the drug alone and/or in combination with sedative/hypnotics, and the likelihood that physical dependence will occur [R].
The Four A's
The goal of opioid therapy is to provide partial analgesia, and maintain or improve function with acceptable side effects. (Four A's: Analgesia, Adverse drug effects, Activity, Adherence) [R].
At each patient visit, the assessment should specifically address these goals (with clear documentation of the 4 A's in the patient's medical record):
- Comfort (degree of analgesia)
- Opioid-related side effects
- Functional status (physical and psychosocial)
- Existence of aberrant drug-related behaviors
Substance Abuse
Patients should be carefully screened for risk of diversion or abuse. The following behaviors suggest relative contraindications to opioid use. With these patients, referral to pain or addiction specialist is advisable [R]:
- History of substance abuse or prior prescription drug misuse
- Unsanctioned dose escalations on several occasions
- Non-adherence to other recommendations for pain therapy
- Unwillingness or inability to comply with treatment plan
- Social instability
- Unwillingness to adjust at-risk activities resulting in serious re-injury requiring additional opioid prescriptions
Random drug screens are one tool to monitor compliance with the opioid regimen. Random urine drug screens are used: (1) To check for diversion, seeking evidence the patient is taking the medication being prescribed; (2) To check for drugs of abuse; and (3) To test for the presence of the prescribed drug. Any evidence of street drug use indicates non-compliance with the opioid contract. The patient's opioids are tapered and he or she is referred to a chemical dependence specialist or treatment program. Primary care physicians need to be aware of the limits of a drug screen. Other useful tools include periodic pill counts or consultation with an addiction medicine specialist.
Evidence of aberrant drug-related behaviors must be carefully assessed. In some cases tapering and discontinuation of opioid therapy will be necessary. Other patients may appropriately continue therapy if the structure for monitoring is tightened. Consideration should be given to consultation with an addiction medicine specialist.
There is not enough evidence to permit generalizable conclusions regarding the abuse of opioids in chronic nonmalignant pain. However, careful patient selection and close monitoring of all nonmalignant pain patients on chronic opioids is necessary to assess effectiveness and watch for signs of abuse. [Conclusion Grade III: See Conclusion Grading Worksheet A -- Annotation #19 (Chronic Pain and Chemical Use) in the original guideline document.]
When there is non-compliance, escalation of opioid use, or increasing pain not responding to increasing opioids, consider whether this represents a response to inadequate pain control (pseudoaddiction, tolerance or opioid-induced hyperalgesia) or a behavioral problem indicating the patient is not a candidate for opioid therapy [M], [R]
Refer to Annotation #19 and Appendix G in the original guideline document for additional information on opioids.
Tricyclic Anti-depressants (TCAs)
Tricyclic anti-depressants have a role in the treatment of neuropathic pain, especially if the patient has co-existing insomnia, anxiety, or depression [A], [M]. TCAs are categorized as secondary amines (nortriptyline or desipramine) or tertiary amines (amitriptyline and imipramine). Both classes are effective in the treatment of neuropathic pain but the tertiary amines have more anticholinergic side effects and generally should be avoided in the elderly.
- Analgesic effects of TCAs are independent of their antidepressant effect and analgesia may be seen with lower doses.
- Start low and increase doses gradually over several weeks to months. Maximum analgesic effect may take several weeks or longer to be seen.
- Baseline electrocardiogram (ECG) is indicated in patients at risk for cardiac adverse effects.
- Common side effects include sedation, dry mouth, constipation, and urinary retention. Use caution in patients with conditions that may be aggravated by TCAs, including heart disease, symptomatic prostatic hypertrophy, neurogenic bladder, dementia, and narrow-angle glaucoma.
See Appendix H, "Pharmaceutical Interventions for Neuropathic Pain" in the original guideline document.
Other (Non-Tricyclic) Anti-depressants
The selective serotonin reuptake inhibitor class of antidepressants has reduced adverse effects compared with TCAs but efficacy in the treatment of neuropathic pain is generally not as good as that shown with TCAs. Bupropion [A], venlafaxine [A], and duloxetine [A] have also shown efficacy in the treatment of neuropathic pain. These drugs can be recommended for patients who do not have adequate response or cannot tolerate TCAs. Duloxetine has been shown to improve pain and global measures of fibromyalgia, compared with placebo [A].
Anticonvulsant or Antiepileptic Drugs
The first generation anticonvulsants carbamazepine and phenytoin are effective in the treatment of neuropathic pain but may have unwanted central nervous system (CNS) side effects. Carbamazepine is approved for the treatment of trigeminal neuralgia and benefits are well established [M].
Pregabalin is indicated for treatment of diabetic neuropathy, postherpetic neuralgia, and fibromyalgia.
Oxcarbazepine is chemically similar to carbamazepine and may have benefits in the treatment of neuropathic pain, including trigeminal neuralgia and diabetic neuropathy.
The second generation agent gabapentin is approved for the treatment of postherpetic neuralgia, but has been shown to have analgesic effects in many cases of neuropathic pain syndromes [A]. To decrease the incidence of adverse effects, which are primarily somnolence and dizziness, start at low doses and titrate up gradually. See also Appendix H, "Pharmaceutical Interventions for Neuropathic Pain", in the original guideline document.
Lamotrigine has efficacy in trigeminal neuralgia, neuropathies associated with human immunodeficiency virus infection, and post-stroke pain.
Topical Agents
Topical lidocaine 5% patches (Lidoderm) are FDA approved for post-herpetic neuralgia and have shown efficacy in other neuropathic pain syndromes. Systemic absorption of lidocaine is minimal and the patch has a clean safety profile with the correct dosage schedule.
Capsaicin, the active ingredient in the herbal product cayenne, is used topically to deplete the pain mediator substance-P from afferent nociceptive neurons. Topical creams and solutions have been used in treating both neuropathic pain and arthritic pain. Capsaicin should be applied for at least six weeks to see full benefits. The side effect of local burning is common and most patients become tolerant after a few days [A], [D], [M].
Refer to the original guideline document for information on muscle relaxants and anti-spasmodics, anxiolytics, and drugs for insomnia.
Intervention Management
Key Points:
- Therapeutic procedures are used to alleviate or reduce chronic pain and should be used in conjunction with a comprehensive treatment plan developed by a chronic pain specialist.
- Interventional techniques should be performed in conjunction with a comprehensive treatment plan that includes pharmacologic, rehabilitative, and psychological interventions.
- Many of the Level I procedures provide both diagnostic and therapeutic benefits, while Level II are reserved for patients who have failed conventional treatment.
- Diagnostic procedures are used to identify neural or musculoskeletal structures that are the source of the patient's pain symptoms.
- The role of intervention modalities is different for chronic pain than acute and should be carefully evaluated by a pain specialist.
Interventional techniques refer to procedures including spinal injections, nerve blocks, spinal cord stimulators, and implantable intrathecal drug delivery systems that are performed in an attempt to diagnose and treat chronic pain. If used alone, the evidence is limited in its success. These procedures should be performed in conjunction with a comprehensive treatment plan that includes pharmacologic, rehabilitative, and psychological interventions. Commonly performed interventional procedures will be categorized as Level I (diagnostic and therapeutic) and Level II (palliative). Many of the Level I procedures provide both diagnostic and therapeutic benefits while Level II interventions are reserved for patients who have failed conventional treatment.
The role of intervention modalities is different for chronic pain than acute and should be carefully evaluated by a pain specialist.
See also Annotation #25, "Level II Management: Interdisciplinary Team Referral, Plus a Pain Medicine Specialist or Pain Medicine Specialty Clinic" below.
Level I Diagnostic Procedures
Examples of commonly performed Level I diagnostic procedures include sacroiliac joint injection, transforaminal epidural injection, and discography.
Level I Therapeutic Procedures
Examples of commonly used Level I therapeutic procedures include facet joint injection, percutaneous radiofrequency neurotomy, intradiscal electrothermal therapy, epidural corticosteroid injections, vertebroplasty and kyphoplasty, and trigger point injections.
Refer to the original guideline document for detailed information on Level I diagnostic and therapeutic procedures.
Complementary Management
Acupuncture
Clinical research with randomized, placebo-controlled trials supports the use of acupuncture for certain chronic pain conditions such as fibromyalgia [A], [M], headache [A], [M], back pain [A], neck pain [A], and osteoarthritis of the knee [A].
Refer to the original guideline document for more information on acupuncture.
Herbal Products Used for Pain
While there are many herbal products used for pain, the following have some supporting data for use in the treatment of pain, but may still have significant potential for drug interactions and adverse effects: Devil's Claw, dimethyl sulfoxide (DMSO), Feverfew, glucosamine and chondroitin, and Willow Bark. DMSO is mentioned due to the frequency of use, despite evidence of toxicity and lack of documented efficacy.
Refer to the original guideline document for more detailed information on herbal products used for pain.