TOPACT GEL 2.5%W/W GEL

Indications

• Osteoarthritis
• Rheumatoid arthritis
• Ankylosing spondylitis
• Acute musculoskeletal pain
• Dysmenorrhea
• Postoperative pain
• Gouty arthritis

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Ketoprofen exerts its effects primarily by inhibiting cyclooxygenase (COX) enzymes, specifically COX-1 and COX-2. This inhibition leads to a decrease in the production of prostaglandins, thereby reducing inflammation, pain, and fever. Additionally, ketoprofen may exert analgesic effects through peripheral and central mechanisms.

Pharmacodynamics

The analgesic and anti-inflammatory effects of ketoprofen are dose-dependent and are attributed to its ability to inhibit prostaglandin synthesis. By reducing the levels of these inflammatory mediators, ketoprofen alleviates pain and reduces swelling. Its effects can be observed within hours of administration, with peak analgesic effects typically occurring within a few hours.

Pharmacokinetics

Ketoprofen is well absorbed following oral administration, with peak plasma concentrations reached within 1 to 2 hours. It is highly protein-bound (approximately 90-95%) and has a volume of distribution of about 0.1 L/kg. The drug undergoes extensive hepatic metabolism, predominantly via glucuronidation, and is excreted primarily in the urine as metabolites, with a half-life ranging from 1.5 to 2 hours.

Contra-indications

• Active peptic ulcer disease
• Severe heart failure
• History of gastrointestinal bleeding or perforation
• Hypersensitivity to ketoprofen or any component of the formulation
• Severe renal impairment
• Pregnancy (especially in the third trimester)

Adverse effects

• Gastrointestinal disturbances (nausea, vomiting, diarrhea, constipation)
• Dizziness or headache
• Rash or other skin reactions
• Increased blood pressure
• Renal impairment
• Hepatic dysfunction
• Cardiovascular events (thrombotic events)

Interactions

• Increased risk of gastrointestinal bleeding with other NSAIDs, corticosteroids, or anticoagulants
• May enhance the effects of antihypertensive medications
• May interfere with the effects of diuretics
• Concurrent use with lithium may increase lithium levels
• Potential increased risk of nephrotoxicity with other nephrotoxic agents

Precautions

• Use with caution in patients with a history of cardiovascular disease
• Caution in patients with asthma or at risk of asthma exacerbation
• Monitor renal function in long-term therapy
• Use with caution in elderly patients due to increased risk of adverse effects
• Discontinue if gastrointestinal symptoms occur

Pregnancy

Ketoprofen should be avoided during pregnancy, particularly in the third trimester due to potential effects on fetal cardiovascular and renal function.

Breast-feeding

Small amounts of ketoprofen may be excreted in breast milk; caution is advised when administered to nursing mothers.

Storage

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

Formulations

• Oral tablets
• Topical gel
• Injectable solution