There isn't one official therapy for PTSD (or an official medication). Ditto
@Hope4Now it's very helpful to find a trauma specialist for one (not just a counselor who did a little EMDR training or a basic CBT therapist who isn't a trauma specialist). CBT works well for many people, but has failed many others. Ditto EMDR...very helpful for some, not for others. I do body psychotherapy for trauma (primarily Somatic Experiencing)...that works well considering my symptoms and complex trauma, including very early trauma. For adult trauma, CBT or EMDR (or a mix) are helpful for many people.
Basically you don't want a therapist who is willing to let you just tell them about your trauma and then you are done. A trauma specialist will help you first work on safety and regulation stuff...developing some positive resources, grounding, etc. Then they will be careful to not push you through memories without being careful to create a retraumatizing scenario. So, trauma specialist or solid background in treating trauma is probably the most important. Depending on the nature of your trauma, your symptoms, and also what is available to you where you are at, you could research CBT for trauma, EMDR, and Somatic Experiencing.
There isn't a one-size-fits-all treatment for trauma, and because of the complicated nature of trauma (and human beings), there might never be. And I think it's good we have some choices. Sometimes you can do a phone interview to find out more about a therapist's process for working on trauma (and they can also learn a little about you and help decide if it's a workable fit). I hope you're able to find a good fit for you.