The Effects of Acetaminophen on Fear

University of Guelph

Status: Completed

Conditions: Fear

Treatments: Drug: Acetaminophen; Other: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT05396677

21-07-024

Details and patient eligibility

About

This study investigates the effects of acetaminophen on behavioral, physiological, and self-report fear responses.

Full description

As acetaminophen blunts the experience of physical, social, and empathic pain, it is important to investigate whether there are other aversive states that the drug also provides relief from. If there are others, this may suggest overlapping mechanisms involved in these affective evaluations, all of which are interrupted by acetaminophen. The emotion of fear is aversive, yet it is distinct from both physical and social pain.

The present study will investigate the effects of acetaminophen on the subjective experience of fear as well as its behavioral outcomes. While blocking adaptive behavioral responses to fear could potentially be problematic in some dangerous situations, it may also be helpful for those with anxiety-related disorders. If individuals on acetaminophen can step farther away from safety on a virtual plank 80 stories above the ground, then perhaps acetaminophen can allow anxious individuals to step farther from their comfort zone in real life. Importantly, if acetaminophen blunts the fear response, this would mean that the drug blocks aversive feelings beyond emotional and physical pain. The extent of its effects will warrant further investigation for a greater understanding of emotional evaluations.

Enrollment: 266 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 18 years or older
• Literate
• Speaks English
• Does not have any risk factors associated with acetaminophen (history of liver or kidney disease, taking other products with acetaminophen, has any allergies to acetaminophen, taking blood-thinning medications, drinks more than 12 alcoholic drinks per week for females, or more than 15 alcoholic drinks per week for males, are/ could be pregnant)
• Has taken acetaminophen in the past without any adverse reactions
• Is not diabetic
• Did not have anything to eat within three hours of study time
• Did not have any acetaminophen or alcohol in the 48 hours prior to study
• Has never had an adverse reaction to virtual reality before, such as headaches or nausea

Exclusion criteria

• Younger than 18
• Non-literate
• Does not speak English
• Has at least one risk factor associated with acetaminophen (history of liver or kidney disease, taking other products with acetaminophen, has any allergies to acetaminophen, taking blood-thinning medications, drinks more than 12 alcoholic drinks per week for females, or more than 15 alcoholic drinks per week for males, are/ could be pregnant)
• Has never taken acetaminophen before
• Diabetic
• Had something to eat within three hours of scheduled study time
• Has had acetaminophen or alcohol in the past 48 hours
• Has had an adverse reaction to virtual reality in the past, such as headaches or nausea

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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266 participants in 2 patient groups, including a placebo group

Acetaminophen Condition

Experimental group

Description:

1000 mg acetaminophen

Treatment:

Drug: Acetaminophen

Placebo Condition

Placebo Comparator group

Description:

1000 mg microcrystalline cellulose

Treatment:

Other: Placebo