What are the recommended medications for acute pain control?

Acute Pain Control Medications

For acute severe pain, use intravenous hydromorphone 0.015 mg/kg as first-line therapy, or fentanyl 1 mcg/kg followed by ~30 mcg every 5 minutes for moderate-to-severe pain; for mild-to-moderate pain, use NSAIDs (ibuprofen 400-600 mg) over codeine-acetaminophen combinations. 1, 2

Severe Acute Pain (IV Route)

Hydromorphone is the preferred first-line agent for severe acute pain requiring intravenous therapy 1, 2:

• Dose: 0.015 mg/kg IV initially 1, 2
• Advantages over morphine: Quicker onset of action, lower risk of toxic metabolite accumulation in renal failure, reduced dose-stacking risk, and physicians are more likely to adequately dose (1.5 mg hydromorphone vs 10 mg morphine psychologically) 1, 2
• Patient-driven protocol: Consider 1 mg + 1 mg hydromorphone dosing, particularly helpful for patients unable to clearly communicate pain levels 1

Fentanyl is recommended over morphine for moderate-to-severe pain 1:

• Dose: 1 mcg/kg initially, then ~30 mcg every 5 minutes 1
• Advantages: Shorter onset of action, 100 times more potent than morphine, higher lipid solubility with better bioavailability, no cross-allergy with morphine 1

If morphine must be used: 0.1 mg/kg IV initially, then 0.05 mg/kg at 30 minutes (maximum 10 mg single dose) 1

Mild-to-Moderate Acute Pain (Oral Route)

NSAIDs are superior to codeine-acetaminophen combinations 1:

• Ibuprofen 400-600 mg every 4-6 hours is the preferred first-line agent 1
• Number needed to treat (NNT): Ibuprofen/naproxen NNT = 2.7 vs codeine-acetaminophen NNT = 4.4-6 1
• Advantages: Longer time to re-medication, safer side effect profile, no CNS depression, avoids CYP2D6 polymorphism issues with codeine metabolism 1

COX-2 selective NSAIDs (celecoxib) are also superior to codeine-acetaminophen 1:

• NNT: Celecoxib 400 mg = 2.5 vs acetaminophen/codeine 600/60 mg = 3.9 1
• Time to re-medication: 8.4 hours vs 4.1 hours 1
• Use with caution in patients with cardiovascular risk factors 1

Oxycodone-acetaminophen is marginally superior to codeine-acetaminophen if opioid combinations are needed 1

Multimodal Approach for Specific Populations

Elderly/Trauma Patients

The 2024 World Society of Emergency Surgery guidelines recommend 1:

• First-line: Intravenous acetaminophen 1000 mg every 6 hours as part of multimodal analgesia 1
• Add NSAIDs cautiously for severe pain, considering adverse events and drug interactions 1
• Multimodal regimen includes: Acetaminophen, gabapentinoids, NSAIDs, lidocaine patches, tramadol, with opioids reserved for breakthrough pain at lowest effective dose for shortest duration 1
• Regional anesthesia: Peripheral nerve blocks for hip fractures, epidural/paravertebral blocks for rib fractures (reduces opioid consumption, infections, delirium) 1

General Acute Pain Management

The 2022 CDC guidelines emphasize 1:

• Nonopioid therapies are at least as effective as opioids for many acute pain conditions including low back pain, neck pain, musculoskeletal injuries, minor surgeries, dental pain, kidney stones, and headaches 1
• Maximize nonpharmacologic therapies (ice, heat, elevation, rest, immobilization) and nonopioid pharmacologic agents (NSAIDs, acetaminophen) 1
• When opioids are necessary: Use immediate-release formulations at lowest effective dose, prescribe "as needed" rather than scheduled dosing, limit to expected duration of severe pain 1
• Avoid extended-release opioids for acute pain—these are indicated only for chronic pain in opioid-tolerant patients 1

Critical Pitfalls to Avoid

Avoid codeine-containing products due to genetic variability in CYP2D6 metabolism causing either inadequate analgesia or toxicity 1, 2

Avoid morphine in renal failure due to accumulation of toxic metabolites and higher risk of respiratory depression from dose-stacking 1, 2

Limit acetaminophen in combination products to avoid hepatotoxicity when large opioid doses are needed—prescribe components separately if necessary 1

Never use long-acting opioids (OxyContin, MS Contin, fentanyl patches, methadone) for acute pain—these are for opioid-tolerant chronic pain patients only 1

For patients on methadone or buprenorphine maintenance: Continue maintenance therapy and add short-acting opioids for acute pain, or split methadone dosing to every 6-8 hours for analgesic effect 1