A Patient Has Been Taking Phenobarbital for 2 Weeks as Part

A patient has been taking phenobarbital for 2 weeks as part of his therapy for epilepsy. He tells the nurse that he feels tense and that "the least little thing" bothers him now. Which is the correct explanation for this problem?

A) These are adverse effects that usually subside after a few weeks.
B) The drug must be stopped immediately because of possible adverse effects.
C) This drug causes the rapid eye movement (REM) sleep period to increase, resulting in nightmares and restlessness.
D) This drug causes deprivation of REM sleep and may cause the inability to deal with normal stress.