Therapy isn't exactly a one size fits all solution, it should be used in conjuction with other things such diet, exercise and other self-improvement methods. They might prescribe medication but I doubt it would make much of a difference to artifically change your mood, because it would just make you feel worse or have side effects.
Another thing is that therapy in many places is quite bad, mental health institutions are often overwhelmed by the large amounts of people they have to process as well as tailoring to their specific problems, this isn't a regular illness where everyone just takes the same medication to get treated, there's a lot of fucking factors that are in play to affect a persons mental wellbeing and not all of them can be changed, and depend from person to person, it's quite retarded to assume therapy alone can fix everything because a person can always choose NOT to get treatment as did ER, he had tons of treatment but nothing ever happened, hell he felt even worse because of it.