Scariest? It's a toss up between Invega aka paliperidone (a 2nd generation antipsychotic similar to Risperdal aka risperidone) and Navane aka thiothixene (a 1st generation antipsychotic). The former gave me hyperprolactinemia, which causes lactation and cessation of periods in some women. I believe it also caused a pituitary microadenoma (a pituitary tumor). The endocrinologist told me that if it grew much larger I would need to have it removed by surgery through my nose. Luckily I was finally taken off that med, which also contributed to bad weight gain, and six months later a new MRI showed that the tumor had disappeared.

The latter medication, Navane, was not scary at all until one day I felt and saw the weirdest thing. My lips were puckering completely on their own, an involuntary muscle spasm. I called my psychiatrist quickly. He said it was likely a dystonia, a type of EPS (extrapyramidal symptom).

I'm actually not that easy to scare when it comes to medication side effects. I'm pretty tolerant. The scariest experiences I have had relating to my bipolar disorder have been manic episodes with mixed features and psychosis.

What medication (bipolar or other) gave you the most numerous side effects, and how many? List only if you like.