Extremely disturbing dreams. Help.

Due to medicinal effects my sister is constantly feeling drowzy and often closes her eyes as she feels difficult to open them for long specially close to the timing of medicine. But as soon as she falls asleep she starts having nightmares that someone is attacking her and threatening her life. She trembles in fear while in these dreams and sometimes slaps herself or grabs her throat  and wakes up afraid and confused. Often feels numb hands and feet and chest pain after getting up. Its been around 20-25 days now with this problem nd medicines doesn't seem to work much in reducing those nightmares which are the main cause of her distress now. She often cries and says that i am tired of these disturbing dreams plz do something to stop them. She can't even sleep properly due to this. She is also having severe constipation where lactulose is not working. And today she is having fever and her hands and legs are not feeling much sensation though she can move them now. Please help.