What are the recommended medications for managing specific pain?

Recommended Medications for Managing Specific Pain

First-Line Approach: Non-Opioid Analgesics

For mild to moderate pain, acetaminophen (paracetamol) should be the initial medication of choice, with NSAIDs as an alternative or addition when acetaminophen alone is insufficient. 1

Acetaminophen (Paracetamol)

• Acetaminophen 500-1000 mg every 4-6 hours is the safest first-line agent with fewer side effects than NSAIDs, providing effective analgesia for approximately 50% of patients with acute pain 1, 2, 3
• Maximum daily dose is 4-6 grams (4000-6000 mg), with lower dosing recommended for patients with liver disease 1
• Onset of action occurs within 15-30 minutes 1
• When used in multimodal therapy, acetaminophen reduces opioid consumption and associated side effects while improving postoperative outcomes 1

NSAIDs (Non-Steroidal Anti-Inflammatory Drugs)

• Ibuprofen 400-600 mg every 6 hours is the safest NSAID option for moderate pain when used alone or combined with acetaminophen 1, 2
• Maximum daily dose: 2400 mg (4 × 600 mg) or 2400 mg retarded formulation (3 × 800 mg) 1
• Other NSAIDs (naproxen 500 mg twice daily, diclofenac 50 mg four times daily, ketoprofen 75 mg four times daily) have similar efficacy but no consistent superiority over ibuprofen 1, 2
• COX-2 selective inhibitors (coxibs) may be considered if gastrointestinal risk is high, but they carry increased cardiovascular risk and higher cost 1
• All NSAIDs require caution regarding gastrointestinal, renal, and cardiovascular toxicity 1

Multimodal Analgesia Strategy

Combining medications from different classes provides superior pain control while minimizing individual drug-related side effects. 1

• Acetaminophen plus NSAIDs together provide additive analgesic effects for mild to moderate pain 1, 4, 5
• This combination should be used before escalating to opioid therapy 1, 5
• Gabapentinoids (gabapentin, pregabalin) can be added as adjuncts in multimodal regimens, particularly for neuropathic pain components 1

Pain Type-Specific Recommendations

Musculoskeletal Pain

• Acetaminophen and NSAIDs are first-line agents for musculoskeletal pain 1
• Acetaminophen has fewer side effects and should be tried first 1
• Tramadol 37.5-400 mg daily (in divided doses) may be used for up to 3 months for osteoarthritis pain when first-line agents fail 1

Cancer Pain

• Follow the WHO analgesic ladder, starting with paracetamol and/or NSAIDs for mild pain 1
• For mild to moderate cancer pain, weak opioids (codeine, tramadol, dihydrocodeine) should be combined with non-opioid analgesics 1
• Oral morphine is the opioid of first choice for moderate to severe cancer pain, starting at 20-40 mg 1
• Oxycodone is 1.5-2 times more potent than oral morphine; starting dose is 20 mg 1, 6
• Analgesics for chronic cancer pain should be prescribed on a regular schedule, not "as needed" 1
• The oral route should be the first choice for administration 1
• Immediate-release opioid formulations must be prescribed as rescue doses for breakthrough pain episodes 1

Neuropathic Pain

• Opioids should not be first-line agents for chronic neuropathic pain in patients living with HIV 1
• Gabapentinoids and tricyclic antidepressants are preferred initial agents for neuropathic pain 1
• Lamotrigine is not recommended for HIV-associated neuropathic pain 1
• Alpha lipoic acid is recommended for chronic HIV-associated peripheral neuropathic pain 1

Postoperative Pain

• Multimodal analgesia should always be considered, with a pharmacological step-up approach including opioids only when necessary 1
• Acetaminophen administered at the beginning of postoperative analgesia may be better and safer than other drugs 1
• Opioid usage should be reduced as much as possible in postoperative pain management strategies 1

Opioid Therapy: When and How

Opioids should be reserved for moderate to severe pain when non-opioid analgesics are inadequate, ineffective, or not tolerated. 1, 7

Initiation and Dosing

• For opioid-naive patients, start with the lowest effective dose: immediate-release oxycodone 5-15 mg every 4-6 hours as needed 7
• Oral morphine 20-40 mg is the standard starting dose for moderate to severe cancer pain 1
• Individual titration using immediate-release formulations every 4 hours plus rescue doses (up to hourly) is recommended 1
• Combine short- and long-acting opioids for optimal control 1

Opioid Conversion

• Hydrocodone is approximately equipotent with oral morphine (conversion factor 1:1) 6
• Oxycodone is 1.5-2 times more potent than morphine 1, 6
• When converting between opioids, use a conservative approach—it is safer to underestimate than overestimate the dose 7
• Example: 30 mg hydrocodone converts to approximately 20 mg oxycodone 6
• Oral to IV/subcutaneous morphine ratio is 1:2 to 1:3 1

Special Populations

• In renal impairment, all opioids should be used with caution at reduced doses and frequency 1
• Fentanyl and buprenorphine (transdermal or IV) are the safest opioids in chronic kidney disease stages 4-5 (eGFR <30 mL/min) 1

Mandatory Adjunctive Measures

• Laxatives must be routinely prescribed for both prophylaxis and management of opioid-induced constipation 1
• Metoclopramide and antidopaminergic drugs should be used for opioid-related nausea/vomiting 1
• Monitor closely for respiratory depression, especially within the first 24-72 hours and after dose increases 7

Critical Pitfalls and Caveats

Acetaminophen

• Hepatotoxicity risk with doses exceeding 4 grams daily or in patients with liver disease 1
• Many combination products contain acetaminophen—verify total daily intake to avoid overdose 4

NSAIDs

• Avoid in patients with gastrointestinal bleeding risk, renal impairment, or cardiovascular disease 1
• COX-2 inhibitors reduce GI risk but increase cardiovascular risk 1

Opioids

• Assess all patients for risk of misuse, diversion, and addiction prior to prescribing 1, 7
• Codeine, propoxyphene, and tramadol have shown poor efficacy and significant side effects for acute pain 2
• Individual variability in opioid metabolism affects response—monitor and adjust accordingly 6, 7
• Proper disposal of unused medications is essential to prevent diversion 5

Combination Therapy

• Unsupervised consumption of over-the-counter products containing acetaminophen, aspirin, or ibuprofen can lead to therapeutic misadventures when combined with prescription medications 4
• Always verify all medications a patient is taking, including OTC products 4