1. Clinical Overview
Flurbiprofen (0.03% w/v) is a topical ophthalmic solution of a potent non-steroidal anti-inflammatory drug (NSAID) belonging to the phenylalkanoic acid derivative class. It is a selective cyclooxygenase (COX) inhibitor used primarily to manage postoperative inflammation and pain following cataract surgery. In the Indian context, it is a widely prescribed, cost-effective alternative to other topical NSAIDs for ophthalmic surgical prophylaxis and treatment.
| Onset | Duration | Bioavailability |
|---|---|---|
| Therapeutic anti-inflammatory effect typically begins within 30 minutes to 2 hours post-instillation. | Approximately 4 to 6 hours per dose, necessitating multiple daily instillations. | Negligible systemic bioavailability (<1%) when used topically in the eye due to minimal absorption into the systemic circulation. |
2. Mechanism of Action
Flurbiprofen is a potent inhibitor of the enzyme cyclooxygenase (COX), specifically COX-1 and COX-2. This inhibition blocks the conversion of arachidonic acid to prostaglandin precursors (prostaglandin G2 and H2). Prostaglandins are key mediators of inflammation, pain, and miosis. By reducing prostaglandin synthesis in ocular tissues, it decreases inflammation (reduces vasodilation, capillary permeability, and leukocyte migration), alleviates pain, and helps maintain mydriasis during surgery.
3. Indications & Uses
- Inhibition of intraoperative miosis during cataract surgery.
- Postoperative inflammation following cataract extraction.
4. Dosage & Administration
Adult Dosage: For inhibition of intraoperative miosis: 1 drop every 30 minutes, beginning 2 hours before surgery (total of 4 drops). For postoperative inflammation: 1 drop in the affected eye(s) 4 times daily, beginning 24 hours after surgery and continuing for 2 weeks.
Administration: Wash hands before use. Tilt head back, pull lower eyelid down to form a pouch. Instill one drop without touching the dropper tip to eye, eyelid, or any surface. Close eyes gently for 1-2 minutes. Apply gentle pressure on the nasolacrimal duct (inner corner of eye) for 1 minute to minimize systemic absorption. Wait at least 5 minutes before instilling any other eye drops.
5. Side Effects
Common side effects may include:
- Transient burning or stinging upon instillation (≥10%).
- Mild conjunctival hyperemia (redness).
- Itching or irritation.
- Blurred vision immediately after instillation.
- Foreign body sensation.
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Oral Anticoagulants (Warfarin, Acenocoumarol) | Increased risk of ocular hyphema and systemic bleeding due to additive antiplatelet effect. | Major |
| Other Topical NSAIDs (e.g., Ketorolac, Nepafenac) | Increased risk of corneal side effects (ulceration, perforation). Avoid concomitant use. | Major |
| Topical Corticosteroids (e.g., Dexamethasone, Prednisolone) | May increase risk of delayed healing and infection. Often used together post-op, but monitor closely. | Moderate |
| ACE Inhibitors (e.g., Ramipril, Enalapril) | Potential attenuation of antihypertensive effect and increased risk of renal impairment. | Moderate |
| Diuretics (e.g., Furosemide) | Increased risk of renal toxicity. | Moderate |
| Aspirin or other Salicylates | Increased risk of gastrointestinal and ocular bleeding. | Moderate |
| Selective Serotonin Reuptake Inhibitors (SSRIs) e.g., Sertraline | Increased bleeding risk. | Moderate |
7. Patient Counselling
- DO wash hands before and after use.
- DO apply gentle pressure on the inner corner of the eye for 1 minute after instillation.
- DO wait at least 5 minutes before using other eye medications.
- DO NOT touch the dropper tip to any surface to avoid contamination.
- DO NOT wear soft contact lenses while using this medication.
- DO NOT drive or operate machinery until blurred vision clears.
- DO NOT discontinue the medication abruptly without consulting your doctor.
8. Toxicology & Storage
Overdose: Topical overdose is unlikely to cause systemic symptoms. Accidental oral ingestion of eye drops may lead to symptoms of systemic NSAID overdose: nausea, vomiting, epigastric pain, headache, dizziness, drowsiness, tinnitus, metabolic acidosis. In severe cases: gastrointestinal bleeding, acute renal failure, respiratory depression, seizures, coma.
Storage: Store at room temperature (15°C to 25°C). Protect from light. Do not freeze. Keep the bottle tightly closed when not in use. Keep out of reach and sight of children. Discard the bottle 4 weeks after first opening. Do not use if the solution is discolored or contains particles.