*Review* **Ethylcellulose–A Pharmaceutical Excipient with Multidirectional Application in Drug Dosage Forms Development**

#### **Katarzyna Wasilewska and Katarzyna Winnicka \***

Department of Pharmaceutical Technology, Medical University of Bialystok, Mickiewicza 2c, 15-222 Bialystok, Poland; katarzyna.wasilewska@umb.edu.pl

**\*** Correspondence: kwin@umb.edu.pl; Tel.: +48-85-7485616

Received: 17 September 2019; Accepted: 15 October 2019; Published: 17 October 2019

**Abstract:** Polymers constitute the most important group of excipients utilized in modern pharmaceutical technology, playing an essential role in the development of drug dosage forms. Synthetic, semisynthetic, and natural polymeric materials o ffer opportunities to overcome di fferent formulative challenges and to design novel dosage forms for controlled release or for site-specific drug delivery. They are extensively used to design therapeutic systems, modify drug release, or mask unpleasant drug taste. Cellulose derivatives are characterized by di fferent physicochemical properties, such as swellability, viscosity, biodegradability, pH dependency, or mucoadhesion, which determine their use in industry. One cellulose derivative with widespread application is ethylcellulose. Ethylcellulose is used in pharmaceutical technology as a coating agent, flavoring fixative, binder, filler, film-former, drug carrier, or stabilizer. The aim of this article is to provide a broad overview of ethylcellulose utilization for pharmaceutical purposes, with particular emphasis on its multidirectional role in the development of oral and topical drug dosage forms.

**Keywords:** ethylcellulose; polymeric material; cellulose derivative; pharmaceutical excipient
