I take it for a different reason (seizure preventative) so can't comment on the MH aspects, but for me the side effects have been insomnia and hugely increased appetite.
For me, it's still beneficial as the alternative to not taking it is worse, but I did find the side effects, especially the insomnia, took a few weeks to get used after I titrated up over about 100mg.
My GP couldn't prescribe temporary sleeping tablets such as zoplicone as I have nocturnal seizures, but said they would have done otherwise so this may be worth looking into if the insomnia is a problem.
I now take 200mg morning and evening and still want to eat everything in sight, but to me it shows at least they are having an effect, unlike other similar meds, so this may be positive for you?
Interestingly (I have just thought this while typing!) have a lot of stress going on in my life atm but have been calmer and less sad than I would expect, so maybe they do also have an effect on my MH.
I hope you get some benefit from them.