Effect of Clonidine on Responses to Imagery Scripts

• Status: Completed
• Trial end date: 2013-08-07
• Target enrollment: 0
• Participant gender: All

Summary

Background:

• Research has shown that clonidine, a drug originally prescribed to treat high blood pressure and some symptoms of opioid withdrawal, can help block stress-induced relapse to heroin and cocaine seeking in rats. However, it does not seem to block cue-induced relapse in rats. Researchers are interested in studying whether clonidine shows the same pattern of effects on stress- and cue-induced cravings for heroin or cocaine in humans.

Objectives:

• To compare the ability of clonidine to reduce stress- and cue-induced cocaine and heroin craving in drug abusers.

Eligibility:

• Individuals between 18 and 55 years of age who are current cocaine or heroin users.

Design:

• This study will consist of two visits: a screening visit to determine eligibility and an experimental/script session.

• Before the script session, participants will provide urine and breath samples for testing. Participants will complete questionnaires to measure their current drug craving and days since last use of cocaine or heroin.

• At the start of the script session, participants will receive a dose of clonidine or placebo as directed by the study researchers. Three hours after dosing, participants will be read four scripts (two neutral, one stress-inducing, and one drug-cue-related) with breaks in between each script. After each script, participants will respond to questions about levels of stress and craving.

• Participants will provide saliva samples immediately before and during the script readings, and will also be measured for skin response to the scripts.

• Phase: Phase 1
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: National Institute on Drug Abuse (NIDA)
• Treatments: Clonidine

Criteria

• INCLUSION CRITERIA:

1. Age between 18 and 55;

2. Evidence of current cocaine and/or heroin use (by self-report) with a minimum lifetime drug-use duration of 1 year and a minimum current drug use of once in the last 30 days;

EXCLUSION CRITERIA:

1. Hypersensitivity to clonidine or any component of the formulation

2. Schizophrenia or any other DSM-IV psychotic disorder; history of anxiety disorder, panic disorder, bipolar disorder; current Major Depressive Disorder

3. Current physical dependence on opioids, cocaine, alcohol, benzodiazepines or other sedative-hypnotic; this is an exclusion criterion because we want to evaluate the ability of clonidine to affect stress- and cue-induced drug craving independent of its effects on drug withdrawal

4. Cognitive impairment severe enough to preclude informed consent or valid responses on questionnaires

5. Pregnancy or breast feeding

6. Severely impaired hepatic function

7. Severely impaired renal function, with CLcr < 10 ml/minute

8. Medical conditions that contraindicate or that could complicate clonidine administration:

1. hypotension (SBP <95 or DBP < 40 mm Hg) over several readings

2. hypertension(SBP >160 mm Hg, DBP >95 mm Hg) over several readings

3. orthostatic hypotension over several readings or as a consequence of any underlying medical disorder (e.g., autonomic insufficiency)

4. bradycardia (heart rate < 50 bpm) over several readings

5. cerebrovascular disease or any history of CVA or transient ischemic attack (TIA)

6. documented coronary disease

7. serious arrhythmia or conduction defect (e.g., second or third degree heart block, atrial fibrillation)

8. sinus node dysfunction, severe bradycardia or symptomatic bradycardia

9. congestive heart failure

9. Medications that could interact adversely with clonidine: antipsychotics; antihypertensives (e.g., beta blockers); antiepileptics; CNS depressants (e.g. barbiturates, benzodiazepines, narcotic analgesics, alcohol, or other sedatives); cyclosporine; oral hypoglycemic agents or insulin; levodopa; tricyclic antidepressants; herbals such as dong quai, ephedra, yohimbe, ginseng, valerian, St. John s wort, kava kava, gotu kola

10. Women who are able to get pregnant and are not abstinent from sexual activity must agree to use a medically effective form of contraception while in the study. Those include:

1. Hormonal contraceptives (birth control pills, injectable hormones, vaginal ring hormones),

2. Surgical sterility (tubal ligation or hysterectomy)

3. IUD

4. Diaphragm with spermicide

5. Condom with spermicide

Women who do not agree to use these medically effective forms of contraception while in the study will be excluded.