What is Dioflon (diclofenac) 500?

What is Dioflon 500 (Diclofenac)

Dioflon 500 is a brand name for diclofenac, a non-steroidal anti-inflammatory drug (NSAID) with analgesic, anti-inflammatory, and antipyretic properties. It contains 500 mg of diclofenac, which is significantly higher than standard diclofenac formulations typically available in 25 mg, 50 mg, and 75 mg dosages 1.

Mechanism of Action

Diclofenac works primarily by inhibiting cyclooxygenase (COX) enzymes:

• Inhibits both COX-1 and COX-2 with relatively equal potency 1
• Blocks prostaglandin synthesis, reducing inflammation, pain, and fever 1
• Has additional mechanisms beyond COX inhibition, including:
  • Potential inhibition of thromboxane-prostanoid receptors
  • Effects on arachidonic acid metabolism
  • Activation of nitric oxide pathways 2

Pharmacokinetics

• Rapid and complete absorption after oral administration 3
• Peak plasma concentrations reached in approximately 1 hour 1
• Extensively bound to plasma proteins (>99%) 1
• Short elimination half-life of approximately 2 hours 1
• Metabolized in the liver and eliminated through urine and bile 3

Clinical Uses

Diclofenac is commonly used for:

• Acute and chronic painful inflammatory conditions 4
• Rheumatoid arthritis
• Osteoarthritis
• Ankylosing spondylitis
• Acute musculoskeletal injuries
• Acute pain conditions including renal and biliary colic 4

Safety Concerns and Precautions

Cardiovascular Risks

Diclofenac carries significant cardiovascular risks:

• Associated with increased risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke 5
• Meta-analyses show diclofenac has a higher cardiovascular risk (RR 1.63,95% CI 1.12-2.37) compared to other NSAIDs like naproxen 5
• Risk increases with duration of use and in patients with cardiovascular disease 5
• Contraindicated for perioperative pain in coronary artery bypass graft (CABG) surgery 5

Gastrointestinal Risks

• Can cause serious gastrointestinal adverse events including inflammation, bleeding, ulceration, and perforation 5
• Elderly patients are at greater risk for serious gastrointestinal events 5

Dosing Considerations

The 500 mg dosage mentioned in "Dioflon 500" is concerning as it exceeds standard dosing recommendations:

• Standard diclofenac dosing ranges from 75-150 mg daily for osteoarthritis and ankylosing spondylitis 5
• For rheumatoid arthritis, typical dosing is 150-200 mg daily 5
• Available in standard formulations of 25 mg, 50 mg, and 75 mg tablets 1

Alternative Treatment Options

For pain management, particularly in patients with cardiovascular risk factors, consider these alternatives:

1. Acetaminophen (paracetamol) - equally effective as NSAIDs for pain relief in many cases with fewer side effects 5
2. Topical diclofenac - effective for knee osteoarthritis with fewer systemic side effects 5
3. Capsaicin - moderate effect on reducing knee pain associated with osteoarthritis 5
4. Non-pharmacological approaches like physical therapy, heat/cold therapy 5

Important Cautions

• The 500 mg dosage is unusually high and may increase risk of adverse effects
• Diclofenac should be used at the lowest effective dose for the shortest duration possible
• Patients with cardiovascular risk factors should consider alternatives when possible
• Regular monitoring for cardiovascular and gastrointestinal adverse effects is essential

Given the high cardiovascular risk profile of diclofenac compared to other NSAIDs, and the unusually high dosage of 500 mg, extreme caution should be exercised when considering this medication, especially for patients with cardiovascular risk factors.