The Danbury Zoning Board of Appeals has approved a drive thru for a pharmacy in the Central Business District.  Main Street Pharmacy is looking to move into a vacant former bank building, which already has a drive thru window.  Typically that convenience isn't allowed on Main Street.  Main Street Pharmacy applied for special permission to the Zoning Board of Appeals, which gave the go-ahead last month.  The drive-through window is for prescription and medical supply pick up only. The average number of customers picking up at the drive-thru window is expected to be three to four per hour. There are two exit driveways onto Main Street. One lane is strictly for the drive-thru window, the second lane is for exiting cars that did not use the drive-thru window. For people exiting the drive thru, there are four car lengths of space from the light. According to the managing partner, who has been involved with this building for 21 years, there have been no accidents with any cars exiting the driveways.