I went to a four-year program that offered Pharmacology every other spring. (Only available to Juniors and Srs, of course.) I did not take the course, but definitely wish that I had.
Even though I work in the OR now and do not give meds the way floor nurses do, when I did work on the floor I was constantly looking up everything I gave. I didn't really know anything about anything.
I think the expectation was that, as a student, you were looking up stuff and learning it that way. That wasn't a great plan, at least for me... there was a time lapse factor between looking up the med then actually starting the job. Plus there just wasn't the volume of med administration and repetition as a student to make me learn anything. I didn't learn anything about meds except calculation until I was constantly giving it on the floor.
Realize that being a new grad will probably be VERY, VERY difficult. (I hope it won't be, but it was one of the hardest, most exhausting times of my life.)
Also realize that one of your MAIN responsibilities in most patient care settings is med administration. Knowing the normal doses, interactions, etc... you are RESPONSIBLE for that. (I bet I had ten med errors the first six months.) The more knowledge you have under your belt before you have the responsibility, the better!! I wonder now how maybe taking the course could have better prepared me for this responsibility. I DEFINITELY LEARNED THE HARD WAY.
Also, be informed that you will more than likely be required to take a med test when you go through nursing orientation. Both hospitals I've worked at have required this of me. (Classes and tests are not over when school is over.) And the test could very easily cover more than just calculations.
As far as grad school, things change. You never know what situation you'll find yourself in. You may one day be single (for whatever reason) and just unable to go to grad school, you may decide that you LOVE the ICU and never want to leave. My school did a better job of preparing me for grad school, when I wish they had prepared me for the JOB.
I think it's obvious that my advice is TAKE the course. As far as the practicality of family issues... trade babysitting time was a good suggestion. Talk to the prof, see if she doesn't post the lecture on the web, maybe she'll be willing to make some kind of arrangement for you to take tests a different time if you study on your own... Pray?
Okay, there's my dissertation on why take Pharm. Happy pronouncing those long words.