Eye ointments are semi-solid preparations intended for sustained drug release.
They are often used for conditions requiring prolonged drug contact, such as dry eye or infections.
Components:
Base: Typically, anhydrous and non-irritating (e.g., petrolatum, lanolin).
Drug: Antibiotics (e.g., erythromycin), anti-inflammatory agents.
Stabilizers and Preservatives: Enhance stability and prevent microbial growth.
Surfactants: Improve drug dispersion (e.g., polysorbates).
Method of Preparation:
Melting the Base: The ointment base is melted under controlled temperature.
Incorporation of Drug: The drug is dispersed or dissolved in the molten base.
Sterilization:
By heat (e.g., autoclaving the finished ointment).
By aseptic incorporation of a sterile drug into a sterilized base.
Filling: The sterile ointment is filled into sterilized tubes under aseptic conditions.
Advantages:
Extended Drug Availability: Sustained release of the API.
Protection of Ocular Surface: Provides a barrier against external irritants.
Examples:
Antibiotic Ointments: Erythromycin ophthalmic ointment.
Lubricating Ointments: Petroleum jelly-based eye ointments.