specific phobias can be treated in a fairly shortish time via systematic desensitisation or flooding.

people can also do a 'crash course' in anxiey management covering such things as the role of diet, exercise, sleep, and specific skills like progressive muscle relaxation.

similarly for sleep difficulties.

sometimes brief educationally focused therapy is useful for people while their meds kick in too...

depends on the nature of the problem (life time traits / habitual ways of coping vs typically very good functioning but specific problem now)