A 38-year-old man with a history of treatment-resistant PTSD has now experienced improvement on quetiapine 300 mg/day, duloxetine 90 mg/day, and zolpidem 10 mg at bedtime. However, he complains of ongoing nightmares and difficulty staying asleep. He was previously initiated on prazosin 3 mg at bedtime, but he experienced intolerable dizziness, and it was discontinued. Can this patient be rechallenged with prazosin? If so, at what dose?

a) No rechallenge is advisable
b) Rechallenge at 1 mg at bedtime
c) Rechallenge at 2 mg at bedtime
d) Rechallenge at 4 mg at bedtime