Accutane for oily skin and scalp acne, is 40mg per day for 30 days enough? I'm a 34 year old male.

The total cumulative dosage needed in general for Accutane is between 8000-16000mg total. Your dose will give you 1200mg total. So, no, generally speaking this will not be enough for a long-term cure. "This answer has been solicited without seeing this patient and
cannot be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."