The Darcy-Weisbach equation 25362 posted actually does handle that, different liquids are addressed with the kinematic viscosity, which is used in calculating the dimensionless friction factor f in that equation.
There's another equation, simpler, but valid only for laminar flow (Reynolds number < 2000) under pressure in circular pipes, called the Hagen-Poiseuille law.
Head loss hL=32v(L/gD2)V
Where
v = kinematic viscosity
L = length of pipe
g = gravitational acceleration
D = inner diameter of pipe
V = average velocity of fluid
Everything else, valves, fittings, static head, etc. still has to be considered the same as if you were using Darcy Weisbach. That's digging back to my university fluid dynamics though, these days I usually just calculate friction losses with software.