I am switching from ambien er after 10 years to belasomra as it was no longer working more than 3-4 hours. I have long term PTSD from terrors at night over a lobg period- 12 years- and take 1 mil xanax 4 times a day. Am I safe at 20 mil belasomra as 10 is not doing one thing and I have heart arrythmea which is worsening from no sleep.