pharmacology??

I have been studying to take my NCLEX PN.....I let my license go in 95...I had bought a restaraunt and was burned out....I am looking forward to passing my exam and beginning nursing again in a long term care facility...(I love old folks!) anyways ...I have been reading the forums and alot of people say ...Know your meds...well uh...they've changed alot since 1996...so if I totally fail the pharmacology part will I still pass if I pass all other areas with flying colors...I am using Saunders comprehensive....I am so freaked out ...I don't know where to begin...if I am using saunders is that going to give me enough med info???