A Patient Has Been Taking Naltrexone (ReVia)as Part of the Treatment

A patient has been taking naltrexone (ReVia) as part of the treatment for addiction to heroin.
Which statement is true in this case?

A) Naltrexone will prevent the patient's cravings for opioid drugs.
B) Naltrexone will work as a safer substitute for the heroin until the patient completes withdrawal.
C) The patient will experience hypertension and severe nausea if the patient takes heroin while on naltrexone.
D) If opioid drugs are used while taking naltrexone, euphoria is not produced; thus, the drug's effects are lost.