Can Anxiety or Medication Affect a Polygraph Examination?

Anxiety, a mental health diagnosis or prescribed medication does not automatically prevent someone from having a polygraph examination. Nor is that information irrelevant. The correct question is one of individual suitability: can the person understand and take part in the procedure, and can the equipment obtain physiological data of sufficient quality for interpretation on that occasion?

This distinction is reflected in the HMPPS Polygraph Examination Policy Framework, reissued in January 2026. That framework governs statutory testing of eligible people on licence in England and Wales; it does not govern private examinations conducted by the Centre for Forensic Neuroscience (CFN). CFN refers to it as a current UK public-policy reference point, not as an endorsement of CFN or its services.

What Does UK Government Polygraph Policy Say About Anxiety and Mental Health?

The January 2026 HMPPS framework says that most people can be examined if they understand the difference between truth and lying, but it requires the examiner to assess suitability. It also states that, in the large majority of cases, a physical or mental health condition, neurodivergence or prescribed medication will not make a person unsuitable. Reasonable adjustments may be appropriate.

Within that statutory HMPPS process, suitability is not decided from a diagnosis alone. The framework describes a three-part assessment:

• Review of available information — the examiner consults the probation practitioner about known physical and mental health information and relevant professional assessments.
• Pre-examination interview and screening — the examiner reviews the person’s current presentation, health information, understanding and ability to participate.
• Acquaintance or practice examination — the examiner checks whether the person can understand and follow instructions and whether health or other factors adversely affect the recordings or fitness for examination.

The framework also expects the examiner to review the person on the day. A condition that was manageable when the appointment was arranged may be different on arrival. If illness, acute symptoms or another factor prevents a suitable examination, postponement is an appropriate outcome.

CFN is an independent private provider and does not operate the statutory HMPPS licence regime. Its examinations have a different legal and operational context. The same general principle is nevertheless sound: assess the individual, consider reasonable adjustments that preserve the method, and postpone or decline when the conditions for a reliable and ethical examination are not present.

Anxiety Is Not a Lie Signal

A polygraph examination records physiological activity, commonly including respiration, electrodermal activity and cardiovascular activity. Anxiety can affect every one of those channels. That is precisely why an examiner must consider current anxiety when assessing suitability and data quality.

The instrument does not directly record lying, truthfulness or anxiety. It records bodily responses that can be influenced by attention, salience, cognition, emotion, orienting and other processes. No single rise in heart rate, change in breathing or skin-conductance response is a unique marker of deception.

Nor is a professional examination a comparison with an idealised “calm baseline”. In a Comparison Question Test (CQT), interpretation depends on relative response patterns produced by a structured question sequence and evaluated under the procedure’s validated scoring rules. General nervousness may influence the magnitude, variability and stability of the recordings; the examiner must decide whether the resulting data remain interpretable.

The Concealed Information Test, also called the Guilty Knowledge Test (CIT/GKT), is a different paradigm. It tests recognition of salient information among alternatives and has a different evidential literature from CQT methods. Findings about CIT/GKT recognition should not be presented as though they automatically validate CQT deception decisions.

Anxiety is relevant because it can affect participation and physiological data. It is not, by itself, a lie signal or an automatic reason to exclude someone.

Medication and the Polygraph: Suitability, Not Assumption

Prescribed medication does not automatically exclude someone from a polygraph examination. It may, however, affect cardiovascular, electrodermal or respiratory activity, alertness, attention, movement, comprehension or stamina. The practical questions are what is being taken, at what dose and time, whether the regimen is stable, how the individual responds to it, and whether the examination can meet the required procedure on the day.

An examiner should not make a blanket promise that a medicine has “no effect on validity”. Equally, the presence of a prescription is not proof that useful data cannot be obtained. Disclosure, pre-examination screening, observation and the practice examination support a case-specific decision.

Antidepressants: SSRIs and SNRIs

Antidepressants including SSRIs and SNRIs can be associated with physiological or cognitive effects that vary between people and may change after starting treatment or altering a dose. The examiner should consider the medication, dose, timing, stability, reported side effects and current presentation. A stable prescription may be compatible with examination, but compatibility must be assessed rather than assumed.

Benzodiazepines and Other Sedating Medication

Benzodiazepines and other sedating medicines can affect arousal, attention, memory, coordination and physiological responsiveness. A prescribed, stable regimen is not necessarily an exclusion. Acute use, an uncharacteristic extra dose, marked sedation or difficulty understanding and following the procedure may make postponement necessary.

Beta-Blockers

Beta-blockers such as propranolol and atenolol are relevant because they can alter cardiovascular responding. Their use must be disclosed. The examiner then assesses whether interpretable data can be obtained across the required recording channels under the validated procedure. The answer is not to improvise an informal “reweighting” of whichever channels appear least affected.

ADHD Medication: Stimulants and Non-Stimulants

ADHD medication should be considered individually. Relevant factors include the medicine, dose, timing, treatment stability, the person’s usual response, side effects, and their attention and comprehension on the day. It is not appropriate to claim that stimulant medication makes diagnostic responses “more pronounced” or improves accuracy. For related practical considerations, see our article on neurodiversity and polygraph examinations.

Antipsychotics, Mood Stabilisers and Other Medication

Other prescribed medicines may affect alertness, movement, blood pressure, autonomic responsiveness or cognitive processing. The name of a drug or diagnosis is not enough to decide suitability. The examiner needs the medication history and must assess the individual’s current functioning and the quality of the practice recordings.

Mental Health Conditions Require an Individual Assessment

Anxiety disorders, depression, PTSD and other mental health conditions vary substantially in presentation and severity. A person with a diagnosis may be stable, able to consent, able to understand every question and able to produce interpretable data. Another person with the same diagnosis may be acutely unwell or unable to participate reliably on a particular day.

Generalised Anxiety and Panic

Generalised anxiety may increase apprehension, rumination and physiological variability. A history of panic attacks does not itself preclude an examination, but acute panic can make it impossible to sit still, attend to questions or obtain stable recordings. Clear explanation, familiarisation and measured pacing may help; postponement is appropriate if the person cannot participate or the recordings are not interpretable.

PTSD and Trauma-Related Symptoms

PTSD may involve hyperarousal, dissociation, concentration difficulties or strong responses to reminders of trauma. If proposed questions overlap with traumatic material, the examiner must consider welfare, question suitability and whether the responses can be interpreted within the procedure. The existence of PTSD is not an automatic exclusion, but current symptoms can be decisive.

Depression and Cognitive Effects

Depression can affect energy, concentration, processing speed and physiological responsiveness. The relevant issue is not a diagnostic label or an assumed severity category. It is whether the person can understand, consent, maintain attention and complete the procedure, and whether the data are of sufficient quality on that occasion.

Reasonable Adjustments That Preserve the Method

Reasonable adjustments should support participation without changing the validated test format or scoring rules. Depending on the person and the examination, appropriate measures may include:

• More explanation and familiarisation before data collection, including time to understand the equipment and sequence.
• A controlled, quiet environment with unnecessary distractions reduced. See why the polygraph testing environment matters.
• Breaks compatible with the procedure, placed so they do not undermine a data-collection sequence.
• Clear, reviewed questions that the examinee understands before recording begins.
• Appropriate pacing during explanation and interview while preserving standardised presentation during the recorded sequence.
• Communication or neurodivergence adjustments tailored to identified needs.
• An acquaintance examination to assess understanding, ability to follow instructions and the quality of physiological recordings.
• Postponement when adjustments cannot produce suitable conditions on that occasion.

Collecting extra charts is not a generic way to “compensate” for unsuitable conditions or poor-quality data. Adjustments must remain compatible with the validated procedure and its quality requirements.

A Diagnosis Is Not the Same as Unsuitability

There should be no automatic exclusion list based solely on diagnoses. An examiner may postpone or decline when the person’s current presentation prevents safe participation, informed consent or interpretable recording. Examples include:

• Acute mental-health instability, including severe agitation, mania, psychosis or dissociation that prevents meaningful participation.
• Current welfare or safeguarding concerns. Suicidal thoughts require an assessment of immediate risk and welfare; they should not be treated as a permanent, diagnosis-like exclusion.
• Cognitive or communication barriers that prevent the person from understanding the process or the agreed questions despite reasonable adjustments.
• Acute panic or distress that prevents sustained attention, stillness or completion of the procedure.
• Intoxication, impairment or withdrawal that affects participation or the recordings.
• Inability to provide informed consent in a private examination.
• Physiological recordings that remain uninterpretable during the acquaintance examination or data-quality review.

A recent medication change is information to assess, not an automatic ban. Postponement may be sensible where the person is experiencing new side effects, instability or a material change in functioning. For a broader discussion, see when a polygraph examination should be refused.

What You Should Do Before Your Examination

Do not alter prescribed medication for the purpose of a polygraph examination.

Do not omit, increase or reduce a prescribed dose in an attempt to influence anxiety or the recordings. Follow the instructions of your prescriber. Tell the examiner what you take, the dose and timing, any recent changes, and any side effects relevant to your ability to participate. If you are uncertain about how to take a medicine, seek advice from the clinician or pharmacist responsible for it; a polygraph examiner should not replace medical advice.

1. Provide an accurate medication list, including prescribed, over-the-counter and recently discontinued medicines.
2. Describe recent changes in dose, timing, symptoms or side effects.
3. Explain relevant support needs, including communication, sensory, mobility or neurodivergence adjustments.
4. Raise concerns before the appointment where possible, particularly panic, trauma triggers, cognition or ability to sit still.
5. Read about the process in our guide on how to prepare for a polygraph examination.

CFN’s confidential pre-examination screening questionnaire allows relevant health and medication information to be considered before the appointment.

Self-Medication and Countermeasures

Do not take medication that was not prescribed for you, use alcohol or take an additional sedative in an attempt to “calm down” or change the result. This may create a health risk, impair consent or participation, degrade the data and lead to postponement. Honest disclosure is safer and gives the examiner the information needed to make a defensible suitability decision.

The Key Point: Suitability, Not Diagnosis

The central question is:

Can this individual, in their present circumstances, understand and participate in the examination and produce physiological data capable of reliable interpretation under the validated procedure?

If the answer is yes, anxiety, a mental health diagnosis, neurodivergence or prescribed medication need not prevent the examination. If the answer is no or remains uncertain, the responsible course may be further information, reasonable adjustment, postponement or declining to proceed. That is a suitability decision, not a judgement about character or truthfulness.

Postponing or declining an examination because suitable conditions are absent is responsible professional assessment. It is not a failed polygraph examination.

If you have specific concerns about anxiety, antidepressants, beta-blockers, ADHD medication or another aspect of mental health suitability, you can contact CFN confidentially before booking or complete the pre-examination screening questionnaire.

Reference and Scope Note

HM Prison and Probation Service — Polygraph Examination Policy Framework, reissued January 2026

This HMPPS framework applies to statutory polygraph licence conditions for eligible cases in England and Wales. CFN is a private provider, is not part of HMPPS, and does not imply government approval or endorsement by citing the framework. The CQT and CIT/GKT are distinct procedures; evidence about one should not be transferred to the other without methodological justification.