Causality in the Intentionality Model is in the agency of the child. It is the child who perceives, who apprehends, who constructs the intentional state, who acts to express it, and who interprets what others do (including what they say) to construct a new intentional state.
Nortriptyline, sold under the brand names Allegron, Aventyl, Noritren, Nortrilen, and Pamelor among others, is a tricyclic antidepressant (TCA) used to treat clinical depression. Another licensed use for it is in the treatment of childhood bedwetting. Off-label uses include chronic pain and migraine and labile affect in some neurological disorders.
I have had a disabling tension headache for 20 years. I have tried everything and this is the only medication besides Pamelor that helps dramatically! Its really unpredicable and can have some major side effects (like sedation/intoxication/psychosis) but it does help with my headache noticiably and nothing else does.