While CBT is one of the modalities that can be used to treat insomnia, the length of time it takes to work and how lasting the results will be depend on multiple factors. Your psychologist can conduct an assessment of your specific situation and give you a more specific response. In general, if there arent deeper and more longterm causes for the insomnia, it can be significantly improved within the first 3 months of weekly therapy. You can learn more about insomnia treatment at this link httpsintrospectionbeverlyhills.cominsomniatherapy

A manualized CBT-i treatment takes between 6-8 sessions.

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https://www.utmedicalcenter.org/medical-care/medical-services/procedures-treatments/cognitive-behavioral-therapy-for-insomnia-cbt-i/#:~:text=How%20long%20does%20it%20take,continue%20working%20on%20your%20success.