Hello, I understand your concern for your sister who has been diagnosed to have Bipolar disorder. Now, you have mentioned that she is not improving despite medication, but you haven t mentioned what her current symptoms are, that is, whether she is in a depressive phase or a manic phase. Bipolar disorder has to be treated with mood stabilizer medication. There are different mood stabilizers like Lithium, Valproate, Carbamazepine, etc. So, you have to first ensure that she is on a mood stabilizer. Secondly, the dose of the mood stabilizers must be adequate, so that it controls her symptoms. Mood stabilizers may take a few weeks to bring on their full efficacy. So, if the medication has been started recently, you can wait for more time. Sometimes, medical conditions like Hypothyroidism can lead to poor treatment response or treatment resistance. So, ensure that all such medical conditions are ruled out Finally, if there is still no improvement, then she needs a thorough re-evaluation of her diagnosis. Best wishes.