Usage
- Nepafenac is prescribed for the treatment of pain and inflammation associated with cataract surgery. It is also used to reduce the risk of postoperative macular edema (swelling in the back of the eye) following cataract surgery, especially in diabetic patients.
- Pharmacological Classification: Nonsteroidal anti-inflammatory drug (NSAID).
- Mechanism of Action: Nepafenac is a prodrug that is converted to amfenac, a non-selective inhibitor of cyclooxygenase (COX) enzymes. COX enzymes are responsible for producing prostaglandins, which mediate inflammation and pain. By inhibiting COX, nepafenac reduces the production of prostaglandins, thereby alleviating pain and inflammation in the eye.
Alternate Names
- Nepafenac ophthalmic suspension
- Nepafenac ophthalmic solution
- Nepafenac eye drops
- Brand Names: Nevanac, Ilevro
How It Works
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Pharmacodynamics: Nepafenac, after being converted to amfenac in the eye, inhibits COX-1 and COX-2 enzymes, reducing prostaglandin synthesis and thus decreasing ocular pain and inflammation.
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Pharmacokinetics:
- Absorption: Nepafenac is administered topically as eye drops. It penetrates the cornea and is rapidly hydrolyzed by intraocular hydrolases to amfenac, its active form. Systemic absorption is minimal.
- Metabolism: Amfenac undergoes extensive metabolism in the eye and liver to more polar, inactive metabolites.
- Elimination: Primarily through hepatic metabolism, with negligible amounts eliminated through the kidneys.
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Mode of Action: Inhibits COX-1 and COX-2 enzymes.
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Receptor Binding/Enzyme Inhibition: Inhibits COX-1 and COX-2 enzymes.
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Elimination Pathways: Hepatic metabolism and subsequent elimination.
Dosage
Standard Dosage
Adults:
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Nevanac (0.1%): One drop in the affected eye(s) three times daily, starting 1 day before cataract surgery, continuing on the day of surgery, and for the first 2 weeks of the postoperative period. Treatment can be extended up to 3 weeks postoperatively, as directed by the clinician. An additional drop should be administered 30 to 120 minutes prior to surgery.
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Ilevro (0.3%): One drop in the affected eye(s) once daily, starting 1 day before cataract surgery, continuing on the day of surgery, and for the first 2 weeks of the postoperative period. An additional drop should be administered 30 to 120 minutes prior to surgery.
For reducing postoperative macular edema after cataract surgery in diabetic patients: One drop three times daily, starting 1 day before surgery and continuing for up to 60 days postoperatively.
Children:
- The safety and efficacy of nepafenac have not been established in children under 10 years old. Its use is not recommended in this age group. For children 10 years and older, consult product guidelines.
Special Cases:
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Elderly Patients: No dosage adjustments are generally necessary.
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Patients with Renal Impairment: No dosage adjustment is needed as systemic exposure is low.
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Patients with Hepatic Dysfunction: No dosage adjustment is needed as systemic exposure is low.
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Patients with Comorbid Conditions: Patients with diabetes, rheumatoid arthritis, dry eye syndrome, or corneal abnormalities should be monitored closely for potential corneal complications.
Clinical Use Cases
Nepafenac is specifically indicated for pain and inflammation associated with cataract surgery, including the reduction of macular edema risk after surgery in diabetic patients. Its clinical use cases outside of this context are limited. Dosing in other settings would be considered off-label use and should be under careful consideration of a physician.
Dosage Adjustments
No specific dosage adjustments are routinely recommended, though caution is advised in patients with certain conditions.
Side Effects
Common Side Effects:
- Foreign body sensation
- Dry eye
- Eyelid swelling, crusting
- Increased tearing
- Blurred vision
- Headache
Rare but Serious Side Effects:
- Corneal complications (keratitis, corneal melting)
- Increased intraocular pressure
- Endophthalmitis (infection inside the eye)
- Anterior uveitis (inflammation of the iris)
- Hyphema (bleeding in the eye)
Long-Term Effects:
- Corneal complications (keratitis, corneal melting) with prolonged use, particularly in high-risk patients.
Adverse Drug Reactions (ADR):
- Severe allergic reactions (anaphylaxis)
Contraindications
- Hypersensitivity to nepafenac, any of the excipients, or other NSAIDs.
- Patients with a history of asthma, urticaria, or acute rhinitis precipitated by aspirin or other NSAIDs.
Drug Interactions
- Anticoagulants/antiplatelet drugs (e.g., warfarin, clopidogrel): Increased risk of bleeding
- Corticosteroids (e.g., prednisone): May increase risk of corneal complications
- Other topical ophthalmic medications: Administer at least 5 minutes apart.
Pregnancy and Breastfeeding
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Pregnancy Safety Category: C (Animal studies have shown adverse effects. Risk cannot be ruled out in humans. ) Use not recommended unless benefits clearly outweigh risks.)
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Fetal Risks: Potential for dystocia, increased postimplantation loss, reduced fetal weight and growth, and reduced fetal survival. Nepafenac crosses the placenta.
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Breastfeeding: It is unknown if nepafenac is excreted in human milk. However, since systemic exposure is negligible after topical ocular administration, the risk to a nursing infant is considered low. Nepafenac can be used during breastfeeding. Consider punctal occlusion for 1 minute or more after administering drops.
Drug Profile Summary
- Mechanism of Action: Inhibits COX-1 and COX-2 enzymes, reducing prostaglandin synthesis and inflammation.
- Side Effects: Foreign body sensation, dry eye, blurred vision, headache, corneal complications, increased intraocular pressure.
- Contraindications: Hypersensitivity to nepafenac or other NSAIDs; aspirin-induced asthma, urticaria, or acute rhinitis.
- Drug Interactions: Anticoagulants, corticosteroids, other topical ophthalmic medications.
- Pregnancy & Breastfeeding: Pregnancy category C (use with caution if benefits outweigh risks); compatible with breastfeeding with precautions.
- Dosage: Nevanac (0.1%): 1 drop TID; Ilevro (0.3%): 1 drop daily.
- Monitoring Parameters: Visual acuity, intraocular pressure, corneal status.
Popular Combinations
Often used with other topical ophthalmic medications post-cataract surgery, such as antibiotics and corticosteroids.
Precautions
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General Precautions: Screen for allergies to NSAIDs. Monitor patients with diabetes, rheumatoid arthritis, or dry eye closely for corneal complications. Evaluate ocular surface prior to use.
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Specific Populations: Use with caution in pregnancy if benefits clearly outweigh risks; compatible with breastfeeding (consider punctal occlusion). Not recommended for children under 10.
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Lifestyle Considerations: May cause temporary blurred vision; advise patients to avoid driving or operating machinery until vision clears. Protect eyes from sunlight during treatment.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Nepafenac?
A: Nevanac (0.1%): One drop three times daily; Ilevro (0.3%): One drop daily, both starting 1 day before cataract surgery and continuing for 2 weeks postoperatively. An additional drop should be administered 30-120 minutes before surgery.
Q2: How does Nepafenac work?
A: It’s a prodrug converted to amfenac, which inhibits COX enzymes, reducing prostaglandin production and thereby inflammation and pain.
Q3: What are the common side effects of Nepafenac?
A: Foreign body sensation, dry eye, blurred vision, increased tearing, and headache.
Q4: Is Nepafenac safe during pregnancy?
A: Pregnancy Category C. Not recommended unless benefits clearly outweigh risks. Advise patients to discuss with their doctor.
Q5: Can I use Nepafenac while breastfeeding?
A: Generally considered compatible with breastfeeding. Systemic absorption is low. Consider punctal occlusion following administration.
Q6: What are the contraindications for Nepafenac?
A: Hypersensitivity to nepafenac or other NSAIDs; aspirin-induced asthma, urticaria, or acute rhinitis.
Q7: Does Nepafenac interact with other medications?
A: Yes, it can interact with anticoagulants, corticosteroids, and other topical ophthalmic medications.
Q8: Are there any special precautions for patients with diabetes using Nepafenac?
A: Patients with diabetes, particularly those undergoing cataract surgery, should be monitored for macular edema and corneal complications.
Q9: What should patients be advised about while using Nepafenac?
A: Advise patients to avoid sunlight during treatment, report any vision changes or severe eye discomfort, and avoid touching the tip of the bottle to any surface.
Q10: How long can Nepafenac be used?
A: Typically used for 2 weeks post-cataract surgery but treatment can be extended to 3 weeks for pain and inflammation and up to 60 days for macular edema.
