Like others have said, assuming you were abusing drugs or had problems w/ them when the diagnosis was made, first be absolutely sure its not just the drugs. That means no drugs at all for a good while, though i won't advocate stopping any prescription medications you may be on to treat the disorder, assuming thats what you have.
Secondly, IME, being bipolar allows you to get really high without drugs on ocassion, my manic episodes are ime an addictive state of mind. Same thing with depression, thats more like withdrawing/coming down off your natural high that taken to extreme polarities, will cause a pretty nasty comedown once the episode is over. Physical, emotional, and psychological.
Finally, you have to be very careful with all drugs if you are in fact bipolar. A good chunk of them, offer the possibility of developing severe addictions from self medicating the symptoms, triggers for manic or depressive episodes, and in general are fairly unpredictable in how they will interact with your condition.
I know people with the disorder that use cannabis effectively to self medicate, and for them it seems to work pretty well. Not for me though. I think its a bit safer than most, but still fairly risky if you are bipolar to use often, or as a way to self medicate, both in healthy long term ways that manage the condition (the positive), or just something to abuse to numb/medicate your problems so you don't have to deal with them as much or as severe as they would be without medicating with cannabis.
Stimulants as most have mentioned are just a really bad idea (i'd throw entactogen's in there as well, but only because they are going to be very addictive to someone who is depressed alot and just wants an escape, not the case for all with M/D though) . IMHO, they are drugs that mimic the affects (albeit crudely) of manic depression. You feel better than great, awesome, and able to do anything, and desire can easily get out of control, leading to impulsive feel good addictions to all kinds of things, other drugs, stimulants, and non-drug things as well, food shopping, sex, on and on. Then you come down and you become depressive, depending on your moodswings at the time it can lead to severe depression, and amplify alot of the other symptoms of manic depression.
Psychadelics, are risky, but i would say they can be used safely if you are very careful. My own expirence with them, was at first it was the most wonderful liberating think i had ever embarked upon, and learned alot about myself and how to make some positive changes in terms of bipolarity. Then i kept tripping, did not take those introspections i knew to be true seriously, or act upon them, and started tripping to self medicate. It managed some of my problems, but imho opened another can of worms by doing so. I have not tripped for a little under 2 months for this reason, after tripping 1-2 times a week all summer. Its really hard to work with psychs with M/D since imho, the introspection can be difficult to deal with. Learning how fucked you are, or how you need to change and how hard thats going to be. Its possible to make progress with them, i won't advocate it though due to my own expirence, keep in mind i abused them for a good year or so as well.
Benzos are prob one of the worst, as they will bury your issues until they can no longer be kept inside, or you decide to w/d and it all comes pouring out on top of the hell that is benzodiazepine withdrawal. I won't say its not wise to have them on hand, but be EXTREMELY cautious, and do not get addicted. Doing so will be worse than the horror stories you hear from benzo w/d in people without the condition by a considerable degree. I wish i never touched them, outside of the rare ocassion i needed to calm down during a bad trip, or have them for friends in the same situation, basically a fire extinguisher only used in emergencys.
Opoids, are a mixed bag imho. Traditional/synthetic opiates, present a very real risk of addiction, but help with the depression. That makes them very dangerous. I would say kratom may be possible to use responsibly to self medicate the condion in a healthy way, i've heard a good deal of anecdotal evidence of others doing so, but it can present the same trap as opiates.
Disassociateves, as well a mixed bag. I'd steer clear of MXE since it has DRI properties (think coke, methyl/ethyl phenidate stimulant territory to an extent), but theres research conducted/being conducted in ketamine and other Arylcyclohexylamines in regards to treatment of depression. Don't use that as a rationalization to take them though. Its research, not statistically backed up theories at this time. Not that they might be useful, they just are another way to throw you into a m/d episode if not used correctly, or in some individuals at all.
TLDR summary-
If you really are bipolar or manic/depressive, be extremely careful with all psychoactive drugs. They can easily be triggers for episodes, maskers of the symptoms by just numbing it away instead of facing it head on, or distort your sense of &/ perspective on reality due to most of them being triggers for episodes, along with the chance of psychosis for some individuals/drugs.
I won't say they shouldn't or should be used either way, just know what is helping/not making it worse, and what is an escape from dealing with the problems, or something that just amplify what is already there, stimulants are the drug that does that the most for me. Being bipolar makes that responsibility harder, take certain drugs irresponsibly, and its a very steep hole to climb out of to get back to where you started before using.
