I'm a 54 year old male sufferer of debilitating bi-polar depression and of significant symptoms of ADD. I work with a psychologist for talk therapy, and I've also been working with psychiatrist for helpful meds.

Over six years, the psychiatrist and I have been incrementally trying and tweaking doses of different meds to find a combo that works for me. My depression has finally responded well to a daily mix of five different meds (Effexor, Wellbutrin, Buspiron, Lamictal and Adderoll).

Five meds everyday is obviously a lot, but it's the only combination that has given me great relief from the depression. I can get out of bed, be more productive than before and not experience weeping spells day and night.

Nevertheless, I still suffer from episodes of the mania part, and I experience an almost constant state of energy draining anxiety impacting my work, social life and basic daily demands of life. I try to relax, meditate, take things slower, but I don't succeed in controlling it.

The psychiatrist has now suggested I consider trying 100mg of Neurontin (Gabapentin). This would be on top of the other five meds I take. Neurontin is apparently known for very low potential of side-effects. However, all the meds I take each already share overlapping low-level potential for the same side-effects. These side-effects include significant weight-gain, drowsiness, dizziness, kidney damage and even sudden life-threatening conditions.

I've been lucky so far not to have any of these reactions. However, I'm worried that adding Neurontin to my daily cocktail might put my system over the top for suddenly experiencing one or more of these side-effects.

I asked my psychologist about my concern, but he can't predict any specific increase of risk, just says try it and see what happens. If he doesn't know, or it can't yet be known, then I guess I take the risk of adding the sixth med.

I'm just wondering, at least in general, if several meds of any kind that share low-potential for the same side-effects, when taken together, increase the odds of experiencing it. Is it math of increasing the odds in total? Is it in theory or practice a reasonable concern? Has anyone been in this situation with the same concerns as I have?