DOLAREN INJECTION

Indications

• Osteoarthritis
• Rheumatoid arthritis
• Ankylosing spondylitis
• Acute pain
• Chronic pain conditions
• Menstrual pain
• Post-operative pain

Dosage

Children: Refer to the BNF for Children for age-appropriate dosing recommendations.

Adults: Refer to the BNF for specific dosing guidelines based on condition and patient factors.

Mechanism of action

Diclofenac primarily exerts its effects by inhibiting cyclooxygenase (COX) enzymes, particularly COX-2, which decreases the production of prostaglandins from arachidonic acid. This action results in decreased inflammation, pain, and fever.

Pharmacodynamics

The pharmacodynamic effects of diclofenac include analgesic, anti-inflammatory, and antipyretic properties. The onset of analgesia is typically seen within a few hours after administration, while the anti-inflammatory effects may take several days to reach their maximum. Its efficacy in managing pain is comparable to other NSAIDs, with a favorable safety profile when used appropriately.

Pharmacokinetics

Diclofenac is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring approximately 1 to 2 hours after oral administration. It is extensively metabolized in the liver, primarily via cytochrome P450 enzymes, and has a half-life of about 1 to 2 hours. The drug and its metabolites are excreted mainly through the kidneys, with a small percentage eliminated through bile.

Contra-indications

• Active peptic ulcer disease
• Severe heart failure
• Severe renal impairment
• Hypersensitivity to diclofenac or other NSAIDs
• History of gastrointestinal bleeding or perforation related to previous NSAID therapy

Adverse effects

• Gastrointestinal discomfort
• Nausea
• Vomiting
• Diarrhea
• Constipation
• Headache
• Dizziness
• Hypertension
• Renal impairment
• Hepatic dysfunction
• Skin reactions

Interactions

• Anticoagulants may increase the risk of gastrointestinal bleeding
• Other NSAIDs may increase the risk of adverse effects
• Diuretics may have reduced efficacy
• ACE inhibitors may have reduced efficacy
• Lithium levels may be increased

Precautions

• Use with caution in patients with a history of cardiovascular disease
• Monitor renal function periodically during long-term use
• Use with caution in elderly patients due to increased risk of adverse effects
• Avoid in patients with a history of gastrointestinal disorders

Pregnancy

Use during pregnancy only if the potential benefit justifies the potential risk to the fetus. Avoid use in the third trimester due to the risk of premature closure of the ductus arteriosus.

Breast-feeding

Use with caution during breastfeeding, as diclofenac is excreted in breast milk.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Oral tablets
• Topical gel
• Rectal suppositories
• Intramuscular injection