I'd like to point out to anyone reading this that, it's not always so simple. Maintenance drugs may very well be the best answer for you personally and I don't mean to challenge that - truly, if it works for you that is fantastic - but these drug are certainly not best for everyone who meets a bipolar diagnosis. i.e. :'That'll happen' isn't always the case if the maintenance drug is tapered off under professional supervision. In the context of bipolar I, since that seems to be what we're discussing, taking drugs for maintenance, especially (but not only) antipsychotics, may result in some undesirable and unintended side effects. Especially if you've only had one episode, you will want to carefully discuss the pros and cons with your doctor.

Bipolar disorder uprooted my entire life and so I took maintenance drugs in order to prevent another episode. After 2yrs I have tapered off of antipsychotics and my experience has been actually a marked reduction in the severity and duration of mood disturbances (both of which used to be quite severe) & my physical health has greatly improved. Specifically, I used to be at 9% body fat and had gained 65 lbs - not a harmless side effect (e.g. I was pre-diabetic). I'm now halfway back to my old BF%. There needs to be a distinction between taking drugs sometimes even lifelong in hopes to prevent an episode, and taking them in a prodromal phase or acute manic episode, where they have been proven. The problem lies in that not every person is able to recognize the signs of mania or hypomania, so it's simpler to just dish out maintenance meds in hope that it works. Whenever I say this, people assume that I'm anti-drug, but I'm not saying that.. I just try to dissuade people from thinking that it's a 'fix-everything' pill.

Source: pharmacology student w/ 3 yrs of BP-1