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GENERAL PRINCIPLES OF USE is a topic covered in the Harrison's Manual of Medicine.

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  1. Most treatment failures are due to undermedication and impatience. For a proper medication trial to take place, an effective dose must be taken for an adequate amount of time. For ADs, antipsychotics, and mood stabilizers, full effects may take weeks or months to occur.
  2. History of a positive response to a medication usually indicates that a response to the same drug will occur again. A family history of a positive response to a specific medication is also useful.
  3. Pts who fail to respond to one drug will often respond to another in the same class; one should attempt another trial with a drug that has a different mechanism of action or a different chemical structure. Treatment failures should be referred to a psychiatrist, as should all pts with psychotic symptoms or who require mood stabilizers.
  4. Avoid polypharmacy; a pt who is not responding to standard monotherapy requires referral to a psychiatrist.
  5. Pharmacokinetics may be altered in the elderly, with smaller volumes of distribution, reduced renal and hepatic clearance, longer biologic half-lives, and greater potential for CNS toxicity. The rule with elderly pts is to “start low and go slow.”
  6. Never stop treatment abruptly, especially true for ADs and anxiolytics. In general, medications should be slowly tapered and discontinued over 2–4 weeks.
  7. Review possible side effects each time a drug is prescribed; educate pts and family members about side effects and need for patience in awaiting a response.

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Loscalzo, Joseph, et al., editors. "GENERAL PRINCIPLES of USE." Harrison's Manual of Medicine, 19th ed., McGraw Hill Inc., 2017. harrisons.unboundmedicine.com/harrisons/view/Harrisons-Manual-of-Medicine/623496/all/GENERAL_PRINCIPLES_OF_USE.
GENERAL PRINCIPLES OF USE. In: Loscalzo J, Jameson JL, Longo DL, et al, eds. Harrison's Manual of Medicine. 19th ed. McGraw Hill Inc.; 2017. https://harrisons.unboundmedicine.com/harrisons/view/Harrisons-Manual-of-Medicine/623496/all/GENERAL_PRINCIPLES_OF_USE. Accessed April 21, 2019.
GENERAL PRINCIPLES OF USE. (2017). In Loscalzo, J., Jameson, J. L., Longo, D. L., Hauser, S. L., Fauci, A. S., & Kasper, D. L. (Eds.), Harrison's Manual of Medicine. Available from https://harrisons.unboundmedicine.com/harrisons/view/Harrisons-Manual-of-Medicine/623496/all/GENERAL_PRINCIPLES_OF_USE
GENERAL PRINCIPLES of USE [Internet]. In: Loscalzo J, Jameson JL, Longo DL, Hauser SL, Fauci AS, Kasper DL, editors. Harrison's Manual of Medicine. McGraw Hill Inc.; 2017. [cited 2019 April 21]. Available from: https://harrisons.unboundmedicine.com/harrisons/view/Harrisons-Manual-of-Medicine/623496/all/GENERAL_PRINCIPLES_OF_USE.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - GENERAL PRINCIPLES OF USE ID - 623496 ED - Loscalzo,Joseph, ED - Jameson,J Larry, ED - Longo,Dan L, ED - Hauser,Stephen L, ED - Fauci,Anthony S, ED - Kasper,Dennis L, BT - Harrison's Manual of Medicine UR - https://harrisons.unboundmedicine.com/harrisons/view/Harrisons-Manual-of-Medicine/623496/all/GENERAL_PRINCIPLES_OF_USE PB - McGraw Hill Inc. ET - 19 DB - Harrison's Manual of Medicine DP - Unbound Medicine ER -