Post-traumatic stress disorder or PTSD is a specific anxiety disorder that can develop after experiencing a significant traumatic event. Traumatic events can certainly lead to symptoms of depression and anxiety, but PTSD is a specific pattern of symptoms―re-experiencing or reliving the traumatic event (flashbacks or nightmares), avoiding reminders of the traumatic event, hyper-vigilance or over-alertness, and emotional blunting or withdrawal. People with depression or bipolar disorder are more likely to develop PTSD―both because having a mood disorder increases the risk of experiencing a traumatic event and because having a mood disorder makes it more likely a person who experiences a traumatic event will develop PTSD.
For people with bipolar disorder, medication treatment of PTSD is complicated. Several antidepressant medications have been shown to help some people with PTSD. Both sertraline and paroxetine are officially approved as PTSD treatments. But antidepressant medications are risky for people with bipolar disorder; they can cause mania or rapid mood swings. A few of the “atypical” medications sometimes used to treat bipolar disorder (risperidone, olanzapine, and quetiapine) have also been found to help some people with PTSD, but none of the “atypical” medications are officially approved as PTSD treatments. Prazosin, a blood pressure medication, has can help with nightmares and sleep problems in people with PTSD, but it is not officially approved for that purpose. Benzodiazepine (like lorazepam or clonazepam) are often prescribed to people with PTSD, but there is no evidence that they help in the long term. And taking benzodiazepines regularly often leads to dependence. Some types of psychotherapy were specifically developed to help with PTSD. These specific therapies are designed to extinguish or unlearn the link between anxiety symptoms and memories of traumatic events.
You should certainly ask your doctor about PTSD. They will likely ask you some specific questions about the typical symptoms of PTSD. Your doctor might recommend some change in medication, but that will depend on your own personal history. And you should also ask your therapist (if you haven’t already) about types of psychotherapy specifically designed to help with PTSD.