Confidence is not merely an internal feeling. It is a behavioral signal, expressed through eye contact, vocal tone, body posture, and pacing of speech. In socially evaluative contexts, especially those linked to performance or intimacy, small variations in how a person carries themselves can significantly alter the course of interaction. These microbehavioral markers are sensitive not only to anxiety and arousal, but also to expectation: what a person believes about themselves in the moment.
Recent placebo research has shown that what we think we’re taking can measurably change how we act, even when the substance is inert. More surprisingly, these effects persist even under open-label conditions, where participants know they are taking a placebo (Charlesworth et al., 2017). This suggests that expectation and self-narrative, the story we tell ourselves about what we’re capable of, play a powerful role in modulating social presence. Against this background, Cialis (tadalafil), a PDE5 inhibitor used to treat erectile dysfunction, offers a unique case study. While its primary mechanism is vascular, the act of taking it, especially in a low-dose, non-sexual context, may act as a confidence anchor. The hypothesis is not that tadalafil directly improves cognitive performance, but that its symbolic and somatic associations reinforce a psychological shift toward calm assertiveness.
This article explores how the knowledge of taking a pharmacological confidencely active agent, even in the absence of overt physiological changes, can influence social behavior. Through a review of open-label placebo literature, neuropsychological models of expectation, and proposed behavioral experiments, we examine the plausibility, ethics, and translational potential of pharmacological confidence in real-world interactions.
Placebo and “Open Placebo” in Psychiatry: What We Know
The placebo effect, long regarded as a methodological nuisance in clinical trials, is now recognized as a powerful psychobiological phenomenon. In psychiatry and behavioral medicine, placebos are particularly influential, often yielding moderate to large effects in trials for anxiety, depression, and pain-related disorders. Traditionally, these effects were believed to depend on deception – that is, the participant must believe they are receiving an active treatment. However, a growing body of research challenges this assumption through the concept of the open-label placebo (OLP). In OLP studies, individuals knowingly take a pharmacologically inert substance, yet still experience measurable improvements in symptoms. This effect has been demonstrated in randomized trials for conditions as diverse as irritable bowel syndrome, chronic low back pain, and depression (Charlesworth et al., 2017; Kaptchuk et al., 2010). The mechanisms proposed include expectancy formation, conditioning, and embodied cognition, where the act of taking a pill becomes a ritualized behavioral cue that activates cognitive frameworks associated with healing or performance.
In psychiatric contexts, placebo responses are especially pronounced because subjective states such as anxiety or motivation are highly malleable to belief, narrative, and context. Neuroimaging studies have linked placebo responses to changes in prefrontal-limbic circuitry, dopaminergic signaling, and endogenous opioid release, highlighting real neurochemical cascades tied to expectation and trust (Finniss et al., 2010).
The emergence of OLPs presents a new conceptual territory: where transparency does not negate efficacy. This has profound implications for designing ethical, low-risk interventions in psychiatry. It also opens space to examine substances like tadalafil, which are pharmacologically active but may exert psychosocial effects disproportionate to their physiological action, especially when framed by belief, context, and self-association.
Cialis as a “Confidence Anchor”: Psychology of Expectation and Self-Narrative
Tadalafil, widely known under the brand name Cialis, is a phosphodiesterase type 5 (PDE5) inhibitor approved for erectile dysfunction and benign prostatic hyperplasia. Its clinical mechanism (facilitating vasodilation via nitric oxide–cGMP signaling) has well-characterized pharmacokinetics, including a relatively long half-life (~17.5 hours) and slow onset of action (Forgue et al., 2006). However, beyond its physiological action, Cialis also carries a potent psychological narrative: a symbol of preparedness, capability, and male sexual confidence. This symbolic layer creates the conditions for what could be described as a “confidence anchor.” Similar to how athletes perform better when wearing a “lucky” object or after engaging in a familiar ritual, the act of taking Cialis, even when no immediate pharmacodynamic effect is present, can serve as a cognitive cue, reinforcing self-efficacy, social fluency, and perceived attractiveness. In psychological terms, this aligns with the self-signaling theory, which suggests individuals infer their internal states by observing their own actions. Taking a medication associated with confidence may reinforce an internal narrative: “I am ready, I am capable.”
Expectation-based modulation of behavior is well-documented in placebo research. Kirsch’s response expectancy theory posits that anticipated outcomes can directly shape subjective experience and behavior (Kirsch, 1985). In this light, the knowledge of having taken Cialis, especially in a low-dose, non-sexual context, might influence microbehavioral parameters during social interaction: posture, eye contact, vocal tone, and even conversational fluidity.
This dynamic may be further amplified in socially anxious individuals, for whom the symbolic “backing” of a pharmacological agent offers perceived safety in an otherwise threatening environment. Much like open-label placebos, the active awareness of the pill becomes part of the internal story, shaping how one interprets both bodily signals and external social cues.
Taken together, Cialis represents more than a vasodilator; in certain psychological contexts, it may function as a somatically grounded signal of readiness. Understanding this layered pharmacological and symbolic effect provides a rationale for exploring its influence on social behavior, even in the absence of erectile dysfunction.
Field Experiment Design: Microsocial Interactions, Eye-Tracking, Voice Analysis, Posture, Pause Density
To test the hypothesis that the knowledge of taking tadalafil can influence social microbehavior, a controlled field experiment can be designed combining biometric monitoring and observational coding. The central aim is to capture changes in nonverbal and prosodic markers of confidence, such as gaze behavior, vocal intonation, posture, and speech fluency, during brief, socially evaluative interactions.
Participants would be assigned to open-label tadalafil (5 mg) or open-label placebo, administered two to three hours prior to a standardized interaction task. These tasks could include mock job interviews, speed-dating simulations, or impromptu speeches. The interactions would be recorded and analyzed using:
Eye-tracking technology to measure fixation duration, gaze stability, and saccadic patterns (as markers of social attention and threat scanning) (Hirsch et al., 2011).
Voice analysis software to assess pitch variability, vocal intonation range, and pause density (known correlates of social dominance and anxiety) (Scherer et al., 2001).
Pose estimation algorithms (e.g., OpenPose) or motion sensors to track body orientation, arm openness, and upper-body sway—indices of nonverbal confidence (Paret et al., 2016).
Self-report measures (e.g., the Liebowitz Social Anxiety Scale, perceived competence VAS, and state confidence scales) would be used to anchor subjective impressions to objective behavior.
This study would not evaluate sexual outcomes. Instead, it focuses on social cognition and presentation, isolating how the act of taking tadalafil absent any sexual context affects how people present themselves and are perceived during social engagement. Importantly, the open-label design mirrors real-world conditions where individuals are aware of the symbolic and physiological associations of the drug.
Separation of Effects: Pharmacodynamics vs. Expectation (Crossover With Active Control)
One of the central challenges in evaluating the behavioral impact of Cialis as a “confidence anchor” lies in distinguishing pharmacological effects from those driven by expectation. Tadalafil has known vasodilatory and systemic effects, but whether it alters social behavior through central mechanisms, peripheral feedback, or pure expectancy is unresolved.
To isolate these components, a four-arm crossover study could be designed:
Open-label tadalafil
Open-label placebo
Blinded tadalafil
Blinded placebo
This design allows for separation of expectancy (open vs. blind) and drug action (active vs. inert). Behavioral outcomes like eye contact, vocal control, posture, and self-report could be compared across conditions to determine whether changes emerge primarily from belief, biological action, or their interaction.
Including biological markers such as heart rate variability (HRV), salivary cortisol, and skin conductance would help clarify whether changes in autonomic arousal correspond with behavioral markers. Prior work in placebo research has demonstrated that expectation alone can influence these systems (Finniss et al., 2010). Critically, this factorial design would test whether knowing one has taken tadalafil produces more measurable shifts in social presence than taking the drug without that knowledge, highlighting the importance of conscious attribution in shaping behavior.
Risks of Interpretation, Ethics, and Privacy
Although the hypothesis that tadalafil may alter social behavior via expectation-driven mechanisms is scientifically intriguing, it introduces important ethical, interpretive, and privacy-related concerns. First and foremost, behavioral changes in domains like eye contact, posture, or intonation are inherently multifactorial and culturally modulated. Overinterpreting subtle biometric shifts as evidence of “confidence” or “dominance” risks reinforcing reductive or gendered stereotypes.
The use of pharmacological agents to modulate social behavior, even indirectly, raises questions about the line between therapy and enhancement. While off-label use of PDE5 inhibitors is legal, encouraging their use for non-medical psychological purposes could lead to implicit coercion, especially in contexts where social performance is linked to success (e.g., dating, sales, or public speaking). There is also concern about individuals using drugs like tadalafil in socially manipulative ways, if such interventions become commercialized as confidence boosters. From a research ethics standpoint, biometric data such as eye-tracking patterns, vocal signatures, and motion capture are highly sensitive and, in combination, potentially re-identifiable. Data governance must include anonymization, storage encryption, and participant consent not only for data collection, but also for future use in machine learning applications.
Lastly, transparency is essential: participants must be fully informed of the symbolic framing of the intervention, the risks of physiological side effects, and the experimental nature of its proposed psychological benefit. Any clinical or consumer messaging derived from such studies must avoid overstating the drug’s efficacy and remain grounded in replicated, contextually appropriate evidence.
Translation to Psychotherapy: Application in Social Fear Contexts
Insights from open-label placebo research and expectancy-driven behavior change may offer new tools for psychotherapeutic treatment of social anxiety. If the act of taking tadalafil, even with full awareness of its intended medical use, can serve as a confidence cue, it may be reframed within therapy as a form of symbolic exposure or behavioral activation. Much like a ritualized “preparation” in exposure therapy, the medication could act as a transitional object, helping clients associate social engagement with a sense of readiness and capability.
Rather than relying on the drug as a long-term crutch, therapists could integrate it briefly into graded exposure hierarchies, pairing use with structured social tasks, and gradually fading reliance as self-efficacy builds. This aligns with narrative therapy principles, where clients reconstruct internal stories of agency and resilience, using bodily actions (such as pill-taking) as narrative anchors.
However, such use must be approached cautiously and ethically. The aim is not enhancement, but cognitive reframing, using pharmacological awareness to scaffold new behaviors, not to replace psychological work.
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