Company Names, addresses, dates:
  Westover Pharmacy, 5841 N. Washington Blvd, Arlington VA (ca.1942-ca.1950) ^1,2

Notes:
The earliest newspaper mention I could find for the Westover Pharmacy in Arlington was from 1942¹, and the last one I could find was from 1950².

Isaac Earl Kerpelman (1907-1999)³ was listed as the proprietor.⁴
Ancestry.com says that Kerpelman was born in Russia, he came to America as a child in 1912, and he went to the University of Maryland School of Pharmacy.
The 1940 US Census said Kerpelman was living in Arlington, working as a pharmacist, but he was a wager earner, not a store owner. But his WW-II draft card from circa 1940 said that he was "In Business for self", with his place of employment listed as "1731 Wilson Blvd - Arlington Va". So it appears he started his own drug store at that address about 1940. Sometime between 1940 and 1942 he moved it to 5841 N. Washington Blvd and named it the Westover Pharmacy.

This is a cardboard fan, front an back shown. On the back, it says: back: WESTOVER PHARMACY / Prescription Druggist / Oxford 3772 - Reg. No. 2303 / 5841 N. Washington Blvd., ARLINGTON, VA.