Usage
- This combination is primarily used as an ophthalmic solution for the short-term treatment of ocular pain and inflammation, such as after cataract surgery or corneal refractive surgery. It is also prescribed for seasonal allergic conjunctivitis.
- Pharmacological Classification:
- Ketorolac: Nonsteroidal anti-inflammatory drug (NSAID) - analgesic, anti-inflammatory
- Hydroxypropyl methylcellulose (HPMC): Lubricant, artificial tears
- Mechanism of Action:
- Ketorolac inhibits prostaglandin synthesis, reducing pain and inflammation.
- HPMC lubricates the ocular surface, providing relief from dryness and irritation.
Alternate Names
- There is no formally recognized single name for this combination product. It is typically referred to as “Ketorolac + HPMC eye drops”.
- Brand Names: Kapiket, and potentially others depending on region and manufacturer.
How It Works
- Pharmacodynamics: Ketorolac exerts its analgesic and anti-inflammatory effects by inhibiting cyclooxygenase (COX) enzymes, thereby reducing prostaglandin production. HPMC increases tear film viscosity and provides lubrication, alleviating dryness and discomfort.
- Pharmacokinetics: Ketorolac, when administered as eye drops, reaches therapeutic concentrations in ocular tissues. Systemically, Ketorolac is well-absorbed, with peak plasma levels reached within 1-2 hours following oral administration. It undergoes hepatic metabolism (primarily via hydroxylation and conjugation) and is renally excreted. HPMC is not systemically absorbed in significant amounts.
- Mode of Action: Ketorolac’s primary mode of action is COX inhibition, preventing the conversion of arachidonic acid to prostaglandins, which are mediators of inflammation and pain. There is no receptor binding or neurotransmitter modulation directly associated with HPMC’s lubricating action.
- Elimination Pathways: Ketorolac is eliminated mainly through renal excretion (approximately 92%), with the remainder eliminated in the feces. HPMC, as an ophthalmic lubricant, is primarily eliminated through tear drainage and not through systemic metabolic pathways.
Dosage
Standard Dosage
Adults:
- Allergic Conjunctivitis: 1 drop in the affected eye(s) once daily.
- Post-Cataract Surgery: 1 drop in the affected eye(s) four times daily beginning 24 hours after surgery and continuing for up to two weeks.
- Post-Corneal Refractive Surgery: 1 drop in the affected eye(s) four times daily, starting after the procedure, as directed by the ophthalmologist.
Children:
- Safety and efficacy in children have not been established conclusively. Ophthalmologists may prescribe modified doses based on individual assessment.
Special Cases:
- Elderly Patients: Generally, no dosage adjustments are necessary, though patients should be monitored closely for adverse effects.
- Patients with Renal Impairment: Systemic ketorolac requires dose adjustment. In cases of severe renal impairment, the use of the ophthalmic formulation should be assessed by an ophthalmologist.
- Patients with Hepatic Dysfunction: Ophthalmic ketorolac should be used with caution in patients with hepatic impairment. Systemic administration may require dose adjustment.
- Patients with Comorbid Conditions: Use with caution in patients with a history of peptic ulcers, bleeding disorders, or asthma.
Clinical Use Cases
- The listed use cases are not typically applicable to the ophthalmic formulation. Systemic ketorolac may be indicated for post-surgical pain management.
Dosage Adjustments
- For ophthalmic use, dosage adjustments are less frequently needed compared to systemic ketorolac. However, in cases of severe renal or hepatic impairment, the ophthalmologist will make a risk-benefit assessment.
Side Effects
Common Side Effects
- Ocular: Transient stinging, burning, or itching upon instillation, blurred vision, eye redness, increased tearing.
- Systemic (with increased usage): Headache, dizziness, drowsiness, gastrointestinal upset.
Rare but Serious Side Effects
- Ocular: Corneal ulceration, perforation, or infection. Systemic: Allergic reactions, gastrointestinal bleeding, kidney problems, increased risk of heart attack or stroke.
Long-Term Effects
- Prolonged use of ophthalmic ketorolac (beyond the recommended period) can increase the risk of ocular complications. Systemic long-term use increases cardiovascular and gastrointestinal risks.
Adverse Drug Reactions (ADR)
- Ocular hypersensitivity, corneal events. Systemic: Anaphylaxis (rare), Stevens-Johnson syndrome (very rare).
Contraindications
- Hypersensitivity to ketorolac, HPMC, or any component of the formulation. Active peptic ulcer disease. Hypersensitivity to aspirin or other NSAIDs. Use immediately prior to or during coronary artery bypass surgery. Advanced renal impairment. Pregnant or breastfeeding women (especially in the third trimester).
Drug Interactions
- Other topical ophthalmic medications, particularly those containing preservatives. Anticoagulants (e.g., warfarin), other NSAIDs, antihypertensives, lithium, methotrexate.
Pregnancy and Breastfeeding
- Pregnancy Safety Category: C (first and second trimesters), D (third trimester)
- Use is contraindicated in the third trimester due to the risk of premature closure of the ductus arteriosus. Caution is advised during the first and second trimesters.
- Ketorolac is excreted in breast milk. Its use is generally discouraged in breastfeeding mothers. If essential, consider using it cautiously and monitoring the infant for adverse effects.
Drug Profile Summary
- Mechanism of Action: Ketorolac inhibits COX enzymes, reducing pain and inflammation. HPMC provides lubrication.
- Side Effects: Stinging, burning, blurred vision (ocular), headache, GI upset (systemic).
- Contraindications: Hypersensitivity, active peptic ulcer disease, third-trimester pregnancy.
- Drug Interactions: Other NSAIDs, anticoagulants.
- Pregnancy & Breastfeeding: Contraindicated in the third trimester, use with caution in other trimesters. Discouraged during breastfeeding.
- Dosage: See detailed dosage guidelines above.
- Monitoring Parameters: Ocular health (cornea, intraocular pressure), renal function (with systemic use).
Popular Combinations
- The combination of Ketorolac and HPMC is itself commonly used for post-operative ophthalmic use.
Precautions
- General Precautions: Monitor for any signs of hypersensitivity or adverse reactions. Ensure proper hand hygiene before administering eye drops.
- Specific Populations (See dosage section for additional details.)
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Hydroxypropylmethylcellulose + Ketorolac?
A: The usual adult dose is 1 drop in the affected eye(s) once daily for allergic conjunctivitis, and four times daily for post-operative inflammation after cataract or refractive surgeries.
Q2: What are the common side effects?
A: The most common side effects are transient ocular stinging or burning, blurred vision, and mild discomfort.
Q3: Can this combination be used in children?
A: Safety and effectiveness in pediatric patients haven’t been firmly established, and dosing should be guided by a pediatric ophthalmologist.
Q4: Are there any drug interactions I should be aware of?
A: Inform your patients to disclose all medications they are using, including other eye drops. Be cautious when co-administering with anticoagulants or other NSAIDs.
Q5: Can a pregnant woman use this combination?
A: Its use is contraindicated in the third trimester. For earlier trimesters, caution is advised. Discuss the risk-benefit ratio with the patient and obstetrician.
Q6: What is the maximum duration for which this medication can be used?
A: Generally, limit the use to the shortest duration necessary. For post-surgical use, it’s typically limited to 2 weeks. For allergic conjunctivitis, it depends on the individual patient’s response and clinical course.
Q7: How should I advise patients regarding potential blurred vision after using the drops?
A: Advise patients to refrain from driving or operating machinery until their vision clears after using the eye drops. The blurring effect is usually transient.
Q8: What should a patient do if they experience severe or persistent side effects?
A: Patients should immediately discontinue use and seek ophthalmological consultation if they experience severe or persistent eye pain, vision changes, or signs of an allergic reaction.
Q9: How should this medication be stored?
A: Store at room temperature and protect from light. Advise patients to discard any remaining solution after the recommended usage period.
