Effects of Prazosin on the Attention-Enhancing Effects of Nicotine

NCT03416569 | Withdrawn DMC

• 1 other identifier: HP-00078832
• Study Type: interventional
• Target: N/A
• Locations: 0 countries
• Sites: N/A

Brief Summary

To test whether specific aspects of the attention-enhancing effects of nicotine may be mediated by down-stream activation of alpha1 adrenoceptors, the interaction of nicotine and the alpha1 adrenergic antagonist prazosin on cognitive task performance will be tested in human non-smokers. The effects of a low-dose nicotine patch vs. a placebo patch will be tested in the presence and absence of prazosin over 4 test sessions.

Conditions

no Condition, Basic Science

Outcome Measures

Primary Outcomes (6)

• Spatial Attentional Resource Allocation Task reaction time

  average reaction time of trials with a signal detection response

  5 hrs after patch application (=2.5 hr after ingestion of capsule)

• Spatial Attentional Resource Allocation Task omission errors

  percentage of trials on which no response was registered

  5 hrs after patch application (=2.5 hr after ingestion of capsule)

• Rapid Visual Information Processing Task hit rate

  percentage of targets detected

  5 hrs after patch application (=2.5 hr after ingestion of capsule)

• Rapid Visual Information Processing Task reaction time

  average reaction time on trials with a correct response

  5 hrs after patch application (=2.5 hr after ingestion of capsule)

• Change Detection Task accuracy

  percentage of correct responses

  5 hrs after patch application (=2.5 hr after ingestion of capsule)

• Change Detection reaction time

  average reaction time across trials

  5 hrs after patch application (=2.5 hr after ingestion of capsule)

Secondary Outcomes (2)

• Blood pressure

  hourly for 8 hours on each test day

• Vital signs: heart rate

  hourly for 8 hours on each test day

Study Arms (1)

Nicotine-Prazosin Interaction Study

EXPERIMENTAL

Over four test days, each participant will be tested with placebo, nicotine alone, prazosin alone, and nicotine + prazosin, in a double-blind sequence.

Drug: Placebo; Drug: Nicotine; Drug: Prazosin; Drug: Nicotine + Prazosin

Interventions

Placebo DRUG

placebo skin patch + placebo capsule

Nicotine-Prazosin Interaction Study

Nicotine DRUG

nicotine patch (7 mg/24 hrs) + placebo capsule

Nicotine-Prazosin Interaction Study

Prazosin DRUG

placebo patch (7 mg/24 hrs) + prazosin capsule (1 mg)

Nicotine-Prazosin Interaction Study

Nicotine + Prazosin DRUG

nicotine patch (7 mg/24 hrs) + prazosin capsule (1 mg)

Nicotine-Prazosin Interaction Study

Eligibility Criteria

• Age: 21 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Aged 21 to 55 years.
• Smoked no more that 40 cigarettes, cigars or cigarillos in lifetime.
• Smoked no cigarettes, cigars or cigarillos in the last year.
• No exposure to any nicotine-containing product in the last month.
• Normal or corrected to normal vision (at least 20/80).

You may not qualify if:

• Pregnant or breast-feeding.
• Drug or alcohol abuse or dependence currently or in the last 2 years.
• DSM Axis I mood, anxiety or psychotic disorder.
• Cardiovascular or cerebrovascular disease.
• Hypertension (resting systolic BP above 150 or diastolic above 95 mm Hg).
• Hypotension (resting systolic BP below 90 or diastolic below 60).
• Bradycardia (heart rate \<60 bpm).
• Impaired liver or kidney function.
• Severe asthma.
• Obstructive pulmonary disease.
• Type I diabetes.
• Use of any centrally active medications.
• Use of any cardiovascular drugs, including blood pressure medications and antiarrhythmics.
• Use of diuretic medication.
• History of or current neurological illnesses, such as stroke, seizure disorders, neurodegenerative diseases, or organic brain syndrome.

Sponsors & Collaborators

• University of Maryland, Baltimore: lead

MeSH Terms

Interventions

Nicotine; Prazosin

Intervention Hierarchy (Ancestors)

Solanaceous Alkaloids; Alkaloids; Heterocyclic Compounds; Pyridines; Heterocyclic Compounds, 1-Ring; Quinazolines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: The study will be double-blind. Only the statistician performing randomization and the dispensing pharmacist will know the sequence of test conditions.
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: Each participant is tested with each of four test conditions, in counterbalanced sequence.

Study Record Dates

• First Submitted: January 24, 2018
• First Posted: January 31, 2018
• Study Start: March 1, 2018
• Primary Completion: January 1, 2019
• Study Completion: January 1, 2019
• Last Updated: August 19, 2019

Record last verified: 2019-08

Data Sharing

• IPD Sharing: Will not share