How do you prepare eye drops?

Ear drops are liquid preparations meant for instillation into the ear. In these preparations, the drug is usually dissolved or suspended in a suitable solvent such as propylene glycol, polyethylene glycol, glycerol, alcohol, and water, or a mixture of these.  Aqueous vehicle is generally not preferred because the secretions in the ear are fatty in nature and as such these do not easily mix with water.

Ear drops are generally used for their cleansing, pain relieving, and antiseptic actions. The main classes of drugs include analgesics like benzocaine, antibiotics like neomycin and chloramphenicol, and anti-inflammatory agents such as cortisone and dexamethasone. Wax-softening agents include hydrogen peroxide and sodium bicarbonate. Ear drops are usually supplied in amber-coloured, glass bottles with a teat and dropper closure or plastic squeeze bottles. 

Example: Chloramphenicol Ear Drops 

Chloramphenicol - 5 g 

Propylene glycol q.s to 100 ml 

Chloramphenicol ear drops may be prepared by dissolving Chloramphenicol in a sufficient quantity of Propylene glycol and finally making up the final volume with it.