I would suggest that triggering mania is not the answer, as mania can be destructive and will be inevitably followed by a depression as bad or worse than the one he's suffering right now. Most times that I've intentionally triggered mania in desperation to escape depression, things have gone very wrong. I'd suggest that he exercise, but that would make me a hypocrite, as I am depressed and deeply want to avoid doing anything, let alone exercise. A month is early; he may adjust to his medications over a longer period. If he doesn't improve, he could ask his doctor to alter his medication.