Can't sleep. not even ambien (zolpidem) works. currently on remeron but don't sleep through the night. wake up with a racing heart even when calm & relaxed. help?

Sleep assessment: You need to rule out medical causes of sleep disruption if these sleep medications are not helping. For example, you may have an underlying sleep apnea or even a silent form of asthma, both of which can disrupt your breathing during sleeo and awaken you. Or you may have an underlying psychological condition affecting your sleep. Make an appointment with a neurologist who specializes in sleep probs.