You're right that suppressive therapy isn't used as often for oral vs
genital herpes. That's because most people with recurrent oral herpes don't have as frequent outbreaks as genital HSV-2; and
oral herpes usually isn't associated with the psychological/social stress of genital, so people's thresholds for effectiveness, cost, and
convenience are differ
ent. But it works just fine--although the dose for effective suppression is higher than for genital HSV-2.