Topical 19-nor-4-androstenediol and 4-Androstenediol are what works (I have not read anything on 1-AD, so I reserve judgement). A lot of the same principles apply: he's gotta eat alot, drink alot (H20), train hard & rest. 5 or 10 lbs gain would be very good.
With a girlfriend that reads this site, he should definitely be on Gear. You already understand how we think, and you probably could give a mean ass injection. He should consider himself lucky. Tell that meathead to go down to TJ and get some gear so he can really grow.