1999 Jeep Cherokee Oil pressure

I own a 1999 Jeep Grand Cherokee, recently while driving my "check guages" light came on. I noticed that the oil pressure dropped when I either slowed down or stopped. While driving the guage read around 45 psi but when I stopped it dropped to around 10 psi. After making it home I let the Jeep cool down and went to crank it again, no problems at all, no drop in pressure. The next day the same thing happened. Any suggestions on a cure for this?