Ok, I found a questionnaire, a basic test for diagnosing BP disorder. You said you didn't notice. Are you two close? Didn't he display any signs of abnormal behaviour
? The link below is a questionnaire of the criteria for a diagnosis of bipolar disorder. You will probably recognize some of the symptoms of mania, you cannot possibly live with a BP and not notice a mania. Depression is usually obvious.
but it's a test many pdocs use a primary screening for the criteria. He must have at least MOST of the symptoms of mania to qualify as bipolar.
The only REQUIREMENT is that he has had at least one manic episode. Without a manic episode, he cannot be diagnosed as bipolar. GPs do not use this test, most, and I say most, pdocs use this to help diagnose it.
Cymbalta is very likely to trigger mania, especially in type I patients, which is what he is, because of the psychotic features with mania, not just hypomania. It is generally not recommended. If a mood stabilizer is used, such as the depakote he is taking, there is a slightly reduced risk, but still very likely with the severity of his mania. It is more customary to prescribe welbutrin and/or Lamictal first. They work extremely well, and have no sexual side effects. Not everyone can take it, tho, everyone's reaction is different. Is he seeing a pdoc (psychiatrist) or GP. It is best he sees a pdoc, since they specialize in mental illnesses. Of course they aren't perfect, no one is, but they are much more likely to get the "cocktail" of meds right, and much quicker. He will probably change meds and combinations of meds several times to balance both mania/depression.
Depakote is almost as good as lithium for stabilizing moods. But the main side effects are weight gain (guaranteed), and possible hair loss. It is safe physically, the liver damage is extremely rare, lithium is much more dangerous, causing kidney and thyroid damage with prolonged use. Remember all meds have side effects, you can't avoid the possibilities, but very dangerous effects are extremely rare. There are a few other options, if he finds he cannot control his weight.