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01-12-2017 | Leading Article

Relationship Between Adherence Rate Threshold and Drug ‘Forgiveness’

Authors: Alan Morrison, Melissa E. Stauffer, Anna S. Kaufman

Published in: Clinical Pharmacokinetics | Issue 12/2017

Abstract

The medication adherence rate (A) is the proportion of prescribed drug doses consumed within a given time period. It is often assumed that there is an adherence rate threshold (A _th) at or above which the therapeutic effect of the medication is maintained. Drug forgiveness (F) is the number of consecutive doses that can be missed while still maintaining a therapeutic effect. At a given value for A, the therapeutic effect of the drug will be continuously maintained if there is no possibility of >F missed doses. Hence, for a once-daily drug prescribed for N days, A _th and F are related by the formula, A _th = (N − F)/N. At adherence rates below A _th the probability of maintaining the therapeutic effect is equal to the probability of there being no instances of >F consecutive missed doses. Since F is a function of the duration of the drug effect (D) and D varies depending on the specific drug’s pharmacokinetic/pharmacodynamic properties, there is no universal A _th applicable to all drugs.

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Title: Relationship Between Adherence Rate Threshold and Drug ‘Forgiveness’
Authors: Alan Morrison
Melissa E. Stauffer
Anna S. Kaufman
Publication date: 01-12-2017
Publisher: Springer International Publishing
Published in: Clinical Pharmacokinetics / Issue 12/2017
Print ISSN: 0312-5963
Electronic ISSN: 1179-1926
DOI: https://doi.org/10.1007/s40262-017-0552-2

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Relationship Between Adherence Rate Threshold and Drug ‘Forgiveness’

Abstract

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

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