What is the proper administration protocol for injection diclofenac (Nonsteroidal Anti-Inflammatory Drug, NSAID)?

Injectable Diclofenac Administration Protocol

Injectable diclofenac should be administered as 75 mg intramuscularly (IM) as the preferred route, with intravenous (IV) administration reserved for hospital settings with appropriate monitoring. 1

Route Selection

Intramuscular injection is the preferred route for injectable diclofenac in most clinical settings, providing rapid and effective analgesia while avoiding the technical complexity and risks associated with IV administration. 1

• IM administration delivers 75 mg per injection and is particularly effective for acute pain conditions including renal colic, postoperative pain, and acute inflammatory conditions. 1, 2
• IV administration carries significant risks of dilution errors and dosing errors, with many serious adverse effects attributed to large IV overdoses. 1
• IV route should be reserved for severe cases not responding to IM diclofenac or hospital settings with appropriate monitoring. 1

Dosing Protocol

Standard Dosing

• 75 mg per injection is the standard dose for both IM and IV routes. 1, 3
• Minimum interval between doses is 12 hours to minimize adverse effects. 1, 3
• Maximum daily dose is 150 mg (two 75 mg doses), which must never be exceeded by any route. 1, 3, 4

IV Administration Technique (When Required)

• Administer by slow infusion to minimize venous irritation. 3
• Lower doses of 18.75-37.5 mg IV boluses every 6 hours have proven efficacy for postoperative pain management when using the HPβCD formulation. 5
• Standard IV dose of 75 mg should be infused over 30-120 minutes when using traditional formulations. 5

IM Administration Technique

• Deep IM injection into the gluteal muscle is the standard approach. 2, 6
• Subcutaneous administration is possible with newer HPβCD formulations and shows comparable tolerability to IM injection. 7

Special Populations

Elderly Patients

• Consider lower initial doses (25-50 mg) and titrate more slowly in elderly patients. 3
• Increased bleeding risk exists in patients over 60 years, particularly with concurrent anticoagulant use. 4

Renal Impairment

• Reduce dose and monitor closely in patients with renal dysfunction. 3
• Consider dose reduction in patients with creatinine clearance <10 mL/min. 1
• Discontinue if BUN or creatinine doubles during treatment. 1

Hepatic Impairment

• Use with caution in patients with hepatic dysfunction. 1
• Discontinue if liver function studies increase to 3 times the upper limit of normal. 1

Critical Contraindications

Absolute contraindications include: 1, 4

• Active peptic ulcer disease
• Severe heart failure
• Liver failure
• History of gastrointestinal bleeding

Use extreme caution in: 1, 4

• History of peptic ulcer disease
• Concomitant anticoagulant therapy (increases bleeding risk 3-6 fold)
• Pre-existing cardiovascular disease
• Compromised fluid status
• Concomitant nephrotoxic drugs

Monitoring Requirements

For Acute/Short-term Use

• Baseline assessment is typically sufficient for healthy patients receiving short-term IM treatment. 1
• Monitor blood pressure and renal function especially at higher doses (>100 mg/day). 4

For Chronic Use (if applicable)

• Monitor every 3 months: blood pressure, BUN, creatinine, liver function studies, CBC, and fecal occult blood. 1

Clinical Pearls and Pitfalls

Common Pitfalls to Avoid

• Never exceed 150 mg total daily dose by any route, as higher doses significantly increase gastrointestinal and renal toxicity without additional benefit. 1, 4
• Never use dosing intervals shorter than 12 hours for standard 75 mg doses. 4
• Do not combine with anticoagulants without close monitoring, as INR increases up to 15% and bleeding risk triples. 1

Specific Clinical Applications

• For acute renal colic: 75 mg IM provides adequate rapid pain relief as first-line treatment. 1
• For acute crystal-induced arthritis: 150 mg daily for 3 days, then 75 mg daily for 3 additional days. 1
• For postoperative pain: Injectable diclofenac significantly reduces opioid requirements and improves pain scores. 1, 5

When to Stop and Switch

• If two NSAIDs are tried in succession without efficacy, switch to another approach to analgesia such as opioid analgesics or non-pharmacologic interventions rather than continuing to trial additional NSAIDs. 1

Pediatric Considerations

Diclofenac is not the preferred IV NSAID in pediatric populations. 4 Alternative agents with established pediatric protocols include:

• Ketorolac at 0.5-1 mg/kg (max 30 mg) 4
• Ketoprofen at 1 mg/kg every 8 hours 4
• Ibuprofen at 10 mg/kg every 8 hours 4