Ocular and systemic pharmacokinetics of lidocaine hydrochloride ophthalmic gel in rabbits after topical ocular administration

Abstract

Lidocaine hydrochloride ophthalmic gel is a novel ophthalmic preparation for topical ocular anesthesia. The study is aimed at evaluating the ocular and systemic pharmacokinetics of lidocaine hydrochloride 3.5 % ophthalmic gel in rabbits after ocular topical administration. Thirty-six rabbits were randomly placed in 12 groups (3 rabbits per group). The rabbits were quickly killed according to their groups at 0 (predose), 0.0833, 0.167, 0.333, 0.667, 1, 1.5, 2, 3, 4, 6, and 8 h postdose and then the ocular tissue and plasma samples were collected. All the samples were analyzed by a validated LC-MS/MS method. The test result showed that the maximum concentration (C max) of lidocaine in different ocular tissues and plasma were all achieved within 20 min after drug administration, and the data of C max were (2,987 ± 1814) μg/g, (44.67 ± 12.91) μg/g, (26.26 ± 7.19) μg/g, (11,046 ± 2,734) ng/mL, and (160.3 ± 61.0) ng/mL for tear fluid, cornea, conjunctiva, aqueous humor, and plasma, respectively. The data of the elimination half-life in these tissues were 1.5, 3.2, 3.5, 1.9, and 1.7 h for tear fluid, cornea, conjunctiva, aqueous humor, and plasma, respectively. The intraocular lidocaine levels were significantly higher than that in plasma, and the elimination half-life of lidocaine in cornea, conjunctiva, and aqueous humor was relatively longer than that in tear fluid and plasma. The high intraocular penetration, low systemic exposure, and long duration in the ocular tissues suggested lidocaine hydrochloride 3.5 % ophthalmic gel as an effective local anesthetic for ocular anesthesia during ophthalmic procedures.

Laser speckle contrast imaging for blood flow monitoring in predicting outcomes after cerebral ischemia-reperfusion injury in mice

“…The formal sample size has not been decided due to insufficient data. However, based on previous studies [ 17 – 19 ], 3–5 mice per group could meet the statistical requirements.…”

The Effectiveness of 2% Lidocaine Gel Compared to 0.5% Tetracaine Eye Drop As Topical Anesthetic Agent for Phacoemulsification Surgery

“…Perception of pain is highly influenced by many factors, including age, gender, race/ethnicity, and education. Similar surgical stimulus might not be perceived as a similar degree of pain for different patients (11). …”

Trabeculectomy Under Augmented Topical Anesthesia

“…28 We included only the patients who had not undergone any previous ocular surgery, so those patients with conjunctival scarring due to previous ocular surgery or any condition that would make dissection difficult or painful may not be suitable candidates for this procedure. Thus, we conclude that trabeculectomy can be done under augmented topical anesthesia with acceptable patient and surgeon comfort and favorable outcomes.…”