Cerates

Cerates are a class of topical pharmaceutical preparations characterized by a wax-containing, fatty base in which an active substance is dispersed. The base typically combines waxes, such as beeswax, with oils to form a firm, occlusive matrix that remains in place on the skin longer than many ointments. The high wax content gives cerates a firmer texture and reduced greasiness, making them useful as protective dressings and for prolonged contact with the treated area.

Medicated cerates include an active drug, such as an anti-inflammatory, antiseptic, or anesthetic agent, incorporated into the wax-oil base. Simple cerates contain no active drug and serve primarily as protective or emollient preparations. Historical formulations have included examples like calomel cerate or zinc oxide cerate, though modern descriptions of such products are often categorized under ointments or pastes with high wax content.

Preparation generally involves melting the wax with oil to create a homogeneous base, dispersing the drug uniformly, and then allowing the mixture to cool and solidify in molds or containers. The resulting semi-solid is spread onto the skin as needed, offering a localized, sustained effect and a barrier against moisture or irritants.

Today, the term cerate is less commonly used in contemporary pharmacopoeias, with many wax-based topical preparations described as ointments or pastes. Nevertheless, cerates remain part of historical and some niche compounding literature, illustrating the range of semi-solid orally and dermally applied dosage forms.