Novain, 4 Mg/Ml, (Oxybuprocaine Hydrochloride)

Novain (oxybuprocaine hydrochloride) is employed as a topical ocular anesthetic for procedures involving the cornea and conjunctiva.

• Diagnostic ocular examinations: provides rapid, reversible anesthesia for slit‑lamp biomicroscopy, tonometry, and fluorescein staining.
• Minor ocular surgical procedures: facilitates anesthesia for foreign body removal, cataract incision, and laser treatments.
• Contact lens fitting: enables comfortable assessment of lens tolerance without pain.

• Oxybuprocaine hydrochloride exerts its anesthetic effect by reversibly binding to voltage‑gated sodium channels on peripheral ocular nerve membranes. This blockade prevents sodium influx required for depolarization, inhibiting initiation and propagation of nerve impulses. The result is a rapid, localized loss of sensation in corneal and conjunctival tissues without systemic nerve involvement.

Oxybuprocaine hydrochloride may cause local ocular reactions and, rarely, systemic effects.

Common Side Effects

• Transient stinging or burning: mild discomfort upon instillation that resolves within minutes.
• Redness of the conjunctiva: mild hyperemia at the application site.
• Tearing: increased lacrimation lasting a short period.
• Blurred vision: temporary visual disturbance that clears as the drug wears off.

Serious or Rare Side Effects

• Allergic reaction: signs such as swelling, rash, or urticaria requiring medical attention.
• Corneal epithelial toxicity: persistent epithelial defects or ulceration needing ophthalmic evaluation.

When using Novain, consider the following precautions.

• Patient history: assess for known hypersensitivity to oxybuprocaine or other ester‑type anesthetics.
• Ocular surface condition: avoid use on compromised corneas, active infections, or severe dry eye.
• Frequency of administration: limit to the minimum number of drops required for the procedure.
• Systemic absorption: caution in patients with cardiovascular disease due to potential systemic effects.
• Concomitant medications: evaluate for use with other topical ocular drugs to prevent additive irritation.
• Store at room temperature: keep below 25°C, protect from light, and retain in the original container.

Potential drug interactions with Novain should be reviewed before use.

Major Interactions (Avoid)

• Systemic vasoconstrictors: concurrent use may increase cardiovascular risk due to additive systemic absorption.
• Other ocular anesthetics: simultaneous administration can lead to excessive corneal anesthesia and delayed healing.

Moderate Interactions (Monitor Closely)

• Anticholinergic eye drops: may reduce tear production, enhancing local irritation.
• Non‑steroidal anti‑inflammatory eye drops: potential for increased ocular surface irritation.
• Beta‑blocker eye drops: monitor intraocular pressure as combined effects may affect ocular physiology.