Desmopressin is given orally as a tablet
and is only for patients over 5 years old. According to the Food
and Drug Administration, nasal spray formulations of Desmopressin (Noctiva, others) are no longer recommended for treatment of bed-wetting due to the risk of serious side effects.
Again, however, I can't stress enough that your friend should be checked by the GP, as an adult , this can signal other issues that need fairly prompt attention.