In the master bath shower we have very little pressure but in the other bath there is lots of pressure. The fixtures in the shower are old could this be the problem. HELP!!

Good morning Vienna,
Have you removed the shower head and checked to see if you have good pressure with it removed? If a one handled shower valve the cartridge inlet ports may be clogged. If you have a two knob shower valve the seats may be blocked. Turn off the water to the valve and open it up. Check for debris and trashin the cartridge or seats. Now, with the valve still open, turn the water back on and flush out the supply lines. Put it all back together and see if it doesn't work better now. Cheers, Tom