Drug Guide
Nepafenac
Classification
Therapeutic: Ophthalmic anti-inflammatory, analgesic
Pharmacological: Nonsteroidal anti-inflammatory drug (NSAID)
FDA Approved Indications
- Prevention of postoperative pain and inflammation following cataract surgery
Mechanism of Action
Nepafenac is a prodrug that penetrates ocular tissues and is converted to amfenac, which inhibits cyclooxygenase (COX-1 and COX-2) enzymes, reducing prostaglandin synthesis and thereby decreasing inflammation and pain.
Dosage and Administration
Adult: One drop in the affected eye(s) once daily, starting 1 day before surgery and continuing the day after surgery, then as directed by the ophthalmologist.
Pediatric: Safety and effectiveness in pediatric patients have not been established.
Geriatric: No specific dosage adjustments are generally necessary, but caution should be exercised in elderly patients due to potential for age-related ocular or systemic comorbidities.
Renal Impairment: No specific dosage adjustments, but caution advised.
Hepatic Impairment: No specific dosage adjustments.
Pharmacokinetics
Absorption: Rapidly absorbed in ocular tissues when administered topically.
Distribution: Primarily ocular tissues; low systemic absorption.
Metabolism: Converted to active amfenac in ocular tissues.
Excretion: Minor systemic absorption, excreted primarily via the renal route.
Half Life: Approximately 1-3 hours in the ocular tissues.
Contraindications
- Hypersensitivity to nepafenac, other NSAIDs, or any component of the formulation.
Precautions
- Use with caution in patients with risk factors for bleeding, during pregnancy and lactation, and in patients with ocular infections.
Adverse Reactions - Common
- Eye pain, headache (Unknown)
- Blurred vision (Unknown)
- Conjunctival hemorrhage (Unknown)
Adverse Reactions - Serious
- Corneal adverse reactions, such as corneal thinning or ulceration (Uncommon)
- Allergic reactions including hypersensitivity (Rare)
Drug-Drug Interactions
- Increased risk of bleeding with concomitant anticoagulants or antiplatelet agents
Drug-Food Interactions
- None significant
Drug-Herb Interactions
- Potential increased bleeding risk with herbal products like ginkgo or garlic
Nursing Implications
Assessment: Assess for ocular irritation, pain, or signs of allergic reaction before and during therapy.
Diagnoses:
- Risk for infection, pain, risk for bleeding.
Implementation: Administer as prescribed, monitor for side effects, educate patient on proper administration.
Evaluation: Evaluate reduction in pain and inflammation, monitor ocular health.
Patient/Family Teaching
- Instruct on proper eye drop technique.
- Advise to report any signs of allergic reactions or ocular discomfort.
- Emphasize importance of adhering to dosing schedule.
Special Considerations
Black Box Warnings:
- None
Genetic Factors: None established.
Lab Test Interference: No known interference.
Overdose Management
Signs/Symptoms: Ocular irritation, systemic NSAID overdose symptoms (nausea, dizziness) rare.
Treatment: Supportive care, ocular irrigation if topical overdose, monitor and symptomatic treatment.
Storage and Handling
Storage: Store at room temperature, away from light and moisture.
Stability: Stable under recommended storage conditions until expiration date.