Police are investigating the robbery of a chemist in western Sydney last night during which two employees had their wrists bound.

About 11.30pm, two men with their faces concealed forced entry into the chemist on Camden Valley Way at Leppington.

The men threatened three employees who were in the store, two men aged 52 and 62 and a 19-year-old woman, and ordered them to get on the floor.

The 52-year-old man and the woman then had their wrists bound.

The men took a sum of cash and an amount of prescription medications before fleeing the scene in a white-coloured utility.

The employees freed themselves and notified police.

Officers from Camden Local Area Command attended and established a crime scene which was examined by specialist forensic officers.

A white utility, believed to be the same car the men used, was found a short time later burnt-out in Allenby Road at Bringelly.

Police are appealing for anyone who witnessed the incident or any suspicious activity to come forward.

Both men are described as being aged in their early twenties and of Caucasian appearance.