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N-Acetyl Cysteine in Pathologic Skin Picking

A Double-Blind, Placebo-Controlled Study of N-Acetyl Cysteine in Pathologic Skin Picking

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01063348
Enrollment
66
Registered
2010-02-05
Start date
2012-09-30
Completion date
2015-07-31
Last updated
2023-02-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Dermatillomania, Neurotic Excoriation, Pathologic Skin Picking, Psychogenic Excoriation

Keywords

N-Acetyl Cysteine, Picking, Impulse Control Disorder, Obsessive Compulsive Disorder

Brief summary

The goal of the proposed study is to evaluate the comparative efficacy of N-acetyl cysteine to placebo in pathologic skin picking. Thirty subjects with pathologic skin picking will receive 12 weeks of double-blind treatment with N-acetyl cysteine or matching placebo. The hypothesis to be tested is that N-acetyl cysteine will be more effective than placebo in patients with pathologic skin picking. The proposed study will provide needed data on the treatment of an often disabling disorder that currently lacks a clearly effective treatment.

Detailed description

Pathologic skin picking involves repetitive, ritualistic, or impulsive picking of otherwise normal skin leading to tissue damage, personal distress, and impaired functioning. Although skin picking has been described in the medical literature for over one-hundred years, it remains a poorly understood psychiatric issue and often goes undiagnosed and untreated. Picking behavior does not by itself suggest a psychiatric disorder. Pathology exists in the focus, duration and extent of the behavior, as well as the reasons for picking, associated emotions, and resulting problems. Patients with PSP report thoughts of picking or impulses to pick that are irresistible, intrusive and/or senseless. These thoughts, impulses, or behaviors also cause marked distress for patients and significantly interfere with other activities. Unlike normal picking behavior, the pathologic form of skin picking is recurrent and usually results in noticeable skin damage. Thirty subjects with pathologic skin picking will receive 12 weeks of double-blind treatment with N-acetyl cysteine or matching placebo. The hypothesis to be tested is that N-acetyl cysteine will be more effective than placebo in patients with pathologic skin picking. The proposed study will provide needed data on the treatment of an often disabling disorder that currently lacks a clearly effective treatment.

Interventions

DRUGN-Acetyl Cysteine

Week 0 (Visit 1) - Week 3 (V2): 1200mg/day (600mg po qam and 600mg po qpm) Week 3 (V2) - Week 6 (V3): 2400mg/day (1200mg po qam and 1200mg po qpm) Week 6 (V4) - Week 12 (V5): 3000mg/day (1200mg po qam and 1800mg po qpm)

DRUGPlacebo

Matching placebo capsules taken in same amount of pills as the active medication.

Sponsors

University of Chicago
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 64 Years
Healthy volunteers
No

Inclusion criteria

1. Men and women age 18-65; 2. Current diagnosis of pathologic skin picking as determined by criteria proposed by Arnold et al. (2001) for at least 6 months duration

Exclusion criteria

1. Unstable medical illness or clinically significant abnormalities on prestudy laboratory tests or physical examination; 2. History of seizures; 3. Myocardial infarction within 6 months; 4. Current pregnancy or lactation, or inadequate contraception in women of childbearing potential; 5. Need for medication other than NAC with possible psychotropic effects or unfavorable interactions with NAC; 6. Clinically significant suicidality (score or 3 or 4 on item 3 of the Hamilton Depression Rating Scale); 7. Lifetime history of DSM-IV bipolar disorder type I, dementia, or schizophrenia or any other DSM-IV psychotic disorder; 8. Current or recent (past 3 months) DSM-IV substance abuse or dependence; 9. Illegal substance use within 2 weeks of study initiation; 10. Initiation of pharmacotherapy, psychotherapy, or behavior therapy from a mental health professional within 3 months prior to study baseline for the treatment of pathologic skin picking; 11. Previous treatment with N-acetyl cysteine; 12. Treatment with investigational medication or depot neuroleptics within 3 months, with fluoxetine within 6 weeks, or with other psychotropics within 2 weeks prior to study baseline; 13. Asthma (given possible worsening of asthma due to NAC)

Design outcomes

Primary

MeasureTime frameDescription
Yale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Once every three weeks during the 12 week study for each subjectThe entire study for an individual subject will last 12 weeks. Every 3 weeks the subject will take the YBOCS for the duration of the 12 weeks. At each of these visits the outcome will be assessed. The minimum score is 0 and the maximum score is 40, with a higher score being more severe skin picking. There are two sub-scales: one for urges (ranges from 0 to 20) and one for behaviors (ranges from 0 to 20). The total of the scores of each of the sub-scales is the total YBOCS score. That is what will be reported.

Secondary

MeasureTime frameDescription
Skin Picking Self Assessment Scale (SP-SAS)Once every three weeks for the duration of the 12 week study for each subjectThe entire study for an individual subject will last 12 weeks. Every 3 weeks the subject will take the YBOCS for the duration of the 12 weeks. At each of these visits the outcome will be assessed. The minimum score is 0 and the maximum score is 48 with higher scores meaning more severe skin picking. The total of all of the questions equals the total reported SP-SAS score.

Countries

United States

Participant flow

Participants by arm

ArmCount
N-Acetyl Cysteine
N-Acetyl Cysteine - 600mg tablets by mouth (dosing 1200mg - 3000mg qd) N-Acetyl Cysteine: Week 0 (Visit 1) - Week 3 (V2): 1200mg/day (600mg po qam and 600mg po qpm) Week 3 (V2) - Week 6 (V3): 2400mg/day (1200mg po qam and 1200mg po qpm) Week 6 (V4) - Week 12 (V5): 3000mg/day (1200mg po qam and 1800mg po qpm)
35
Placebo
Matching placebo taken daily Placebo: Matching placebo capsules taken in same amount of pills as the active medication.
31
Total66

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyLost to Follow-up310

Baseline characteristics

CharacteristicN-Acetyl CysteinePlaceboTotal
Age, Continuous34.9 years
STANDARD_DEVIATION 11.6
34.7 years
STANDARD_DEVIATION 10.5
34.8 years
STANDARD_DEVIATION 11
Any Psychiatric Comorbidity
No
15 participants17 participants32 participants
Any Psychiatric Comorbidity
Yes
20 participants14 participants34 participants
Sex: Female, Male
Female
33 Participants25 Participants58 Participants
Sex: Female, Male
Male
2 Participants6 Participants8 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
9 / 351 / 31
serious
Total, serious adverse events
0 / 350 / 31

Outcome results

Primary

Yale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)

The entire study for an individual subject will last 12 weeks. Every 3 weeks the subject will take the YBOCS for the duration of the 12 weeks. At each of these visits the outcome will be assessed. The minimum score is 0 and the maximum score is 40, with a higher score being more severe skin picking. There are two sub-scales: one for urges (ranges from 0 to 20) and one for behaviors (ranges from 0 to 20). The total of the scores of each of the sub-scales is the total YBOCS score. That is what will be reported.

Time frame: Once every three weeks during the 12 week study for each subject

ArmMeasureGroupValue (MEAN)Dispersion
N-Acetyl CysteineYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 316.1 units on a scaleStandard Deviation 5.9
N-Acetyl CysteineYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 912.4 units on a scaleStandard Deviation 5.8
N-Acetyl CysteineYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 613.9 units on a scaleStandard Deviation 6.3
N-Acetyl CysteineYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 1211.5 units on a scaleStandard Deviation 5.4
N-Acetyl CysteineYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Baseline18.8 units on a scaleStandard Deviation 5.3
PlaceboYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 1214.1 units on a scaleStandard Deviation 7.5
PlaceboYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Baseline17.6 units on a scaleStandard Deviation 4.8
PlaceboYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 317.3 units on a scaleStandard Deviation 5.4
PlaceboYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 616.3 units on a scaleStandard Deviation 6.9
PlaceboYale Brown Obsessive Compulsive Scale (YBOCS) Modified for PSP (NE-YBOCS)Week 915.0 units on a scaleStandard Deviation 7.4
Secondary

Skin Picking Self Assessment Scale (SP-SAS)

The entire study for an individual subject will last 12 weeks. Every 3 weeks the subject will take the YBOCS for the duration of the 12 weeks. At each of these visits the outcome will be assessed. The minimum score is 0 and the maximum score is 48 with higher scores meaning more severe skin picking. The total of all of the questions equals the total reported SP-SAS score.

Time frame: Once every three weeks for the duration of the 12 week study for each subject

ArmMeasureGroupValue (MEAN)Dispersion
N-Acetyl CysteineSkin Picking Self Assessment Scale (SP-SAS)Week 324.8 units on a scaleStandard Deviation 7.2
N-Acetyl CysteineSkin Picking Self Assessment Scale (SP-SAS)Week 921.5 units on a scaleStandard Deviation 10.3
N-Acetyl CysteineSkin Picking Self Assessment Scale (SP-SAS)Week 621.9 units on a scaleStandard Deviation 8
N-Acetyl CysteineSkin Picking Self Assessment Scale (SP-SAS)Week 1219.4 units on a scaleStandard Deviation 8.7
N-Acetyl CysteineSkin Picking Self Assessment Scale (SP-SAS)Baseline28.6 units on a scaleStandard Deviation 6.2
PlaceboSkin Picking Self Assessment Scale (SP-SAS)Week 1224.5 units on a scaleStandard Deviation 9
PlaceboSkin Picking Self Assessment Scale (SP-SAS)Baseline28.6 units on a scaleStandard Deviation 7
PlaceboSkin Picking Self Assessment Scale (SP-SAS)Week 325.5 units on a scaleStandard Deviation 6.2
PlaceboSkin Picking Self Assessment Scale (SP-SAS)Week 625.0 units on a scaleStandard Deviation 8.8
PlaceboSkin Picking Self Assessment Scale (SP-SAS)Week 924.2 units on a scaleStandard Deviation 8.5

Source: ClinicalTrials.gov · Data processed: Mar 2, 2026