B – 26 The Powerful Placebo Effect in Cough: Relevance to Treatment and Clinical Trials

Abstract Objective This review investigates the placebo effect in cough treatments, with attention to the sensory and psychological components influencing perceived efficacy, and implications for clinical trial design and therapeutic practice. Method Studies examining both pharmacologically active (e.g., dextromethorphan, codeine) and inert cough remedies were reviewed, focusing on sensory attributes such as taste, viscosity, and color. Articles were selected from peer-reviewed journals through targeted database searches, prioritizing experimental and placebo-controlled designs. Results The review identifies sensory characteristics—sweet taste, syrup viscosity, warming/cooling sensations, and pill color—as critical factors that enhance placebo responses. These elements create expectations of relief, influencing neural pathways associated with symptom reduction. For instance, sweeter and thicker syrups are perceived as more potent, while pill color shapes expectations (e.g., red/yellow as stimulants). Conclusion The placebo effect significantly contributes to the perceived effectiveness of cough treatments, complicating clinical assessment of active ingredients. Understanding the sensory-psychological interplay in medication response can enhance therapeutic design and optimize patient outcomes. Clinical trials must control for these factors to accurately evaluate drug efficacy.