The Loo is a hot, debilitating wind that sweeps across Western India, particularly Rajasthan in the months of May and June. Heatstrokes are referred to as Loo lagna (लू लगना). Apparently, Hamdard's Rooh-afza is based on a unani recipe for a drink with cooling properties recommended during this time.
I haven't actually read a primary source for this (and in particular, the Rooh-afza connection), but Wikipedia's article is rather well-referenced.
Connotations
Indian connection