Police have charged a man following an alleged armed robbery in Cairns North this afternoon.

It will be alleged around 4:40pm a man entered a medical centre on Sheridan Street armed with knife.

Police will further allege the man demanded a doctor fill out a medical script before fleeing to a nearby pharmacy to obtain the pharmaceuticals.

Officers commenced patrols of the area and a man was taken into custody at the intersection of Lily Street and Sheridan Street just after 6pm.

A 38-year-old Bungalow man has been charged with one count each of armed robbery, fraud, unlawful possession of a weapon (Category M) and possessing dangerous drugs.

He is due to appear in Cairns Magistrates Court on November 7.