Prophylactic means "to guard against" or "preventative." I take carbamazepine, one of the anticonvulsants. It is a mood stabilizer, though I take it to prevent the ocurrence of future episodes, or if they do occur, to reduce their severity. I don't notice any side effects from it, however, the side effects for any medication differ greatly from person to person.
Keep Taking the Tablets
Your doctor will probably put you on a course of prophylactic medication. These are medications that you take all the time that are intended to prevent further episodes. Keep taking the tablets.
Keep taking the tablets. They may, or may not be effective at preventing further episodes. This is not the point. The reason to keep taking the tablets is that it keeps the doctor happy. And if you do get another episode you need a happy doctor; you need a happy doctor immediately; and you need that happy doctor on your side. So you keep taking the tablets.
My friend Bill has a better response than I do to mood stabilizers. Here's what he says about his own experience: "Your saying the main reason to take your mood stabilizer is to placate your doctor is kind of troubling. You had a number of episodes after you started on lithium. I don't think that's common. My frequency of episodes plummeted after I started on mood stabilizers. The only episodes I had after starting on lithium were one when my lithium level was subtherapeutic, and others when I was trying new mood stabilizers that turned out not to work for me."
Keep taking the tablets. I have been taking prophylactic medication for over 30 years. I had episodes during this time. I had my doubts about the efficacy of the medication, but I kept taking it. It had no noticeable effect that I could discern. Recently, when I changed my medical insurance, there was a period when I could not obtain the medication. I doubt it was just a coincidence that my first episode in eight years occurred while I was not taking the tablets. (I should have paid for the medication myself and claimed it back on the insurance later.) I shall keep taking the tablets, probably for ever and ever. Amen.