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Non-opioid analgesics

Last updated: October 4, 2021

Summarytoggle arrow icon

Non-opioid analgesics include nonsteroidal anti-inflammatory drugs (NSAIDs), selective COX-2 inhibitors, and acetaminophen. NSAIDs inhibit cyclooxygenases (COX-1 and COX-2), thereby disrupting the production of prostaglandin, an important mediator of pain and inflammation. Consequently, NSAIDs possess antipyretic, analgesic, and anti-inflammatory effects, and are particularly effective in the management of musculoskeletal pain (e.g., rheumatic disorders, inflammatory joint pain). Side effects include gastrointestinal ulcers and bleeding, increased risk of heart attacks, and renal function impairment. The severity of these side effects is often underestimated because most non-opioid analgesics are easily available OTC. Selective COX-2 inhibitors have similar effects to NSAIDs, but show a lower risk for gastrointestinal side effects. Acetaminophen possesses antipyretic and analgesic effects and is the most commonly used over-the-counter (OTC) oral analgesic drug. It is generally well tolerated, but overdose can result in significant hepatotoxicity with the risk of acute liver failure.

Overview of non-opioid analgesics
Common agents Activity profile Side effects
Nonsteroidal anti-inflammatory drugs (NSAID)
  • Ibuprofen
  • Diclofenac
  • Indomethacin
  • Naproxen
  • Ketorolac
  • Meloxicam
  • Piroxicam
  • Sulindac
  • Aspirin
COX-2 inhibitors (selective NSAID)
  • Increased cardiovascular risk
  • Renal side effects
Other non-opioid analgesics

Agents

Mechanism of action

Effects

Side effects

The risk of an ulcer is 10–15 times higher if NSAIDS and glucocorticoids are administered simultaneously!

Indications

Contraindications

NSAIDs are contraindicated in the second and third trimester as they may cause premature closure of the ductus arteriosus. Furthermore, they can inhibit uterine contractility.

References:[1][9][10]

Agent

  • Celecoxib [11]

Mechanism of action

Effects

Side effects

Indications

Contraindications

seleCOXib:” celecoxib is a selective COX-2 inhibitor.

References:[11][12]

Agent

  • Acetaminophen

Mechanism of action

Effects

Side effects

Indications

Contraindications

  • Severe liver impairment

Maximum daily dose of acetaminophen: 4 g (adults).
References:[12]

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