[iamanders]

Pax!
If I got it right DSM-5 and ICD-10 are the manuals for diagnosing people. These manuals do not speak about how to actually help people after giving them the diagnosis. So who decides what help are person needs (they don't exactly have manuals like DSM for that)?

[spondiferous]

I think it comes down to things that have worked for a majority of people (ie. DBT has been proven to work for BPD, and other things) and what you need personally. Everyone is different. Most doctors or psychiatrists will be able to tell you in a general what types of meds and therapies and other kinds of treatments work for which diagnoses. It's really all just a crapshoot, though. The best way to figure it out is to talk to other people about it, do research, talk to medical professionals, and try the stuff out yourself to see what works. Some people get lucky and find what they need right away. Some people work and work and work and the treatment always seems to be elusive.
There are other things outside of the standard medical profession as well. Many people swear by 'alternative' forms of healing, such as acupuncture, traditional Chinese medicine, naturopathy, herbalism, Reiki, specific diet, etc. Some people use a combination. Some people will only use something that is recommended by a medical doctor (ie psychotherapy, psychotropics) and some people will only go natural.
Ultimately, to answer your question, in most cases you decide. I say 'in most cases' because sometimes when a person is forcefully incarcerated - committed to a psych hospital against their will - they are also forced to comply with whatever treatments are prescribed to them while they are there.

[shezbut]

iamanders,

Treatment depends, in large part, to you (as the Patient). You decide who you think is best to help you. In current Western civilization, psychiatrists (pDoc's) focus on diagnosing and chemically treating patients.

The therapist (T, social worker or psychologist) one chooses has typically specialized in specific areas (such as child psychology, sexual abuse, personality disorders, etc.), or has chosen to be more broad-based style. {With no particular style of psychotherapy techniques used.}

I would advise you (or whoever you're thinking of with this Q) to consider the "problems" and those who specialize in those "types of problems". Go from there...best wishes to you!