the thing with heat is mainly a caution thingy like don't over exercise, don't get dehydrated etc. taking a bus ride is ok, even if it is boiling outside, so long as you keep yourself well hydrated.

if lithium is working for you as a mood stabiliser then i would stick with it, but monitor how the heat affects you. if you start feeling disoriented etc then that is your clue that you're getting too hot, and that you need to seek our ER immediately.

otherwise, you'll be fine, i'm sure.

as for other mood stabilisers, though - epilim works quite well. lamictal is good also, but primarily for managing the depressive stuff. some of the newer atypical antipsychotics (abilify, zyprexa and seroquel) can also be used as mood stabilisers.

lamictal worked best for me, because my main problem is with depression (very rarely get highs). epilim would be my second choice, though.

but lithium really is the gold standard as far as mood stabilisers go, so if it works well for you with few side effects i would stick with it.