There is no required text book. However, two recommendations for general texts are:
Kaplan and Sadock’s Concise Textbook of Clinical Psychiatry
This is an excellent, complete reference that will be helpful in years to come. This is not the expensive two-volume set, but rather an economical paper back version! A bit encyclpediatic for some.
Black and Andreasen’s Introductory Textbook of Psychiatry
This reads like a DSM manual. Provides definitions, basic clinical picture but falls short on actual clinical management. Can be read like a novel in 6 weeks.
Here is a list of some my favorite books/readings in psychiatry with brief bylines:
Psychiatry and Clinical Neuroscience (2011) by Zorumski and Rubin
This is my favorite introductory text on the neurobiology of mental illness. It is not encyclopediatic but rather tries to explain a bit about systems neuroscience as it applies to mental illness.
Handbook of Psychiatric Drug Therapy (2009) by Labbate, et al
Hands down my favorite psychopharmacology text! After reading this you are ready to prescribe and will be more aware of side effects, treatment options and clinical nuances than your colleagues. Tragically this text is getting out of date, but in general it is still high impact reading.
Psychiatric Interviewing: The Art of Understanding (2016) by Shawn Shea
A great general read about psychiatric interviewing. Not keyed to the DSM and thus students can be frustrated, but his overall approach and advice are wonderful. Does include less standard explanations for psychopathology and some terminology can feel dated.
Mind Fixers: Psychiatry’s Troubled Search for the Biology of Mental Illness (2019) by Anne Harrington
Excellent and fair account of the “journey” of modern psychiatric thinking starting in the 19th century institutions and up to the current DSM crisis. This is a non-technical account and thus does not require any deep neurobiologic interest or familiarity with psychoanalytic thought (though both are helpful).