Identifying and addressing pill aversion in adults without physiological-related dysphagia: A narrative review

Abstract

Solid oral dosage forms (SODFs) (often called pills by patients) are the default formulation to treat medical ailments. Beneficial therapeutic outcomes rely on patients taking them as directed. Up to 40% of the population experience difficulties swallowing SODFs, resulting in reduced adherence and impaired therapeutic efficacy. Often associated with children, this also presents in adults with dysphagia, and without any organic dysphagia (non-physiological-related or functional dysphagia). This review aims to identify and appraise current interventions used to screen for and overcome pill aversion in adults with functional dysphagia. A comprehensive search of the literature was conducted. Articles reporting pill aversion in adults aged ≥18 years with no underlying cause, history of, or existing dysphagia were included. Study quality was determined using the STROBE tool for observational studies. A narrative synthesis of the findings was prepared. We identified 18 relevant cohort studies, which demonstrate that pill aversion is a global problem. Perceived ease of and/or SODF swallowability appears to be influenced by female gender, younger age, co-morbidities (e.g., depression), and physical SODF properties. Patients often modify their medicines rather than raise this issue with their healthcare team. Screening for pill aversion is haphazard but controlled postural adjustments, coating SODFs and behavioural interventions appear to be successful solutions. SODF swallowing difficulties are a barrier to effective medication use. Healthcare professionals must recognise that pill aversion is a problem requiring identification through effective screening and resolution by training interventions, appropriate formulation selection or specialist referral.

Keywords: adherence; drug information; medical education; medication safety; pharmacy.

FIGURE 1

PRISMA 2020 diagram of studies included in this review adapted from Page et al.

FIGURE 2

Capsule sizes expressed in millimetres and inches. With permission from LFA Machines Oxford Ltd (https://www.lfacapsulefillers.com/capsule‐size‐chart ).

FIGURE 3

Comparison of size #0 and #00 capsules with common coins to show their scale. Used with permission from LFA Machines Oxford Ltd (https://www.lfacapsulefillers.com/capsule‐size‐chart ).

FIGURE 4

The relationship between SODF characteristics and medication‐taking. Adapted from Shariff et al.

FIGURE 5

A summary of approaches to manage SODF swallowing difficulties. Adapted from Forough et al.