Can smoking marijauna while taking meds for bipolar cause death??

I never smoked marijauna until my 30's slightly after my brother passed away.  I went through a phase afterwards where I abused it a little bit and now only smoke every few months, becasue I don't want the toxins to build up in my body over a period of time, as I think it might have an adverse effect on my body...however, after hearing the horrible stories about Heath Ledger and other people dying because  they mixed the wrong meds/drugs, I have become very concerned about smoking marijauna while on meds for biploar...should I be concerned about this??  Is there a possiblilty that it could lead to death?  I would greatly appreciate it if someone responded...I'd love to get some feedback...