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Introduction to Concepts in Pharmacotherapy

ByShalini S. Lynch, PharmD, University of California San Francisco School of Pharmacy
Reviewed/Revised Apr 2025
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Therapeutic drug selection and response depend upon the indication, characteristics of the drug (eg, efficacy, safety profile, route of administration, route of elimination, dosing frequency, cost), and characteristics of the patient (eg, age, sex, comorbidities, other medications, and sometimes weight, race, genetic factors, or current or planned pregnancy).

Medication errors (eg, prescribing an inappropriate medication, misreading a prescription, administering a medication incorrectly) and drug interactions can also affect response.

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