← Back to Search

Opioid Antagonist

LDN for Complex Regional Pain Syndrome (LDN-CRPS Trial)

N/A
Recruiting
Led By Sean Mackey, MD, PhD
Research Sponsored by Stanford University
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Upper and/or lower extremity CRPS
CRPS for at least 1 year
Must not have
Use of prescription opioid analgesics or illegal opioid use
Timeline
Screening 3 weeks
Treatment Varies
Follow Up approximately 4 weeks after conclusion of treatment.

Summary

This trial is testing whether low-dose naltrexone can help relieve symptoms of complex regional pain syndrome. Participants will be given either LDN or a placebo for a few weeks, and will be asked to come in for several visits, which will include tests, physical assessments, and questionnaires.

Who is the study for?
This trial is for individuals with Complex Regional Pain Syndrome (CRPS) in an arm or leg, who have been on a stable treatment plan for at least 3 months and have had CRPS for over a year. They must meet specific criteria called the Budapest criteria to participate. People allergic to naltrexone or naloxone, using opioid painkillers or illegal opioids, or who are pregnant or planning pregnancy cannot join.
What is being tested?
The study is examining if low-dose naltrexone (LDN) can help relieve symptoms of CRPS compared to a placebo. Participants will be randomly chosen to receive either LDN or a placebo and will attend study visits and fill out questionnaires over several weeks.
What are the potential side effects?
While not specified here, common side effects of low-dose naltrexone may include headaches, trouble sleeping, nausea, fatigue, and dizziness. Placebo typically has no active ingredients but can lead to perceived side effects.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
Select...
I have CRPS in my arms and/or legs.
Select...
I have had CRPS for at least one year.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
Select...
I use prescription painkillers or have used illegal opioids.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~approximately 4 weeks after conclusion of treatment.
This trial's timeline: 3 weeks for screening, Varies for treatment, and approximately 4 weeks after conclusion of treatment. for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Changes in pain severity

Side effects data

From 2015 Phase 2 trial • 110 Patients • NCT01303835
67%
Fatigue
59%
Hyperglycemia
54%
Platelet count decreased
37%
Constipation
33%
Anemia
33%
White blood cell decreased
31%
Lymphocyte count decreased
30%
Hypocalcemia
30%
Aspartate aminotransferase increased
30%
Alanine aminotransferase increased
28%
Nausea
28%
Hypokalemia
19%
Hyponatremia
17%
Neutrophil count decreased
17%
Hypoalbuminemia
15%
Headache
15%
Anorexia
13%
Insomnia
11%
Postnasal drip
11%
Blood bilirubin increased
11%
Seizure
11%
Vomiting
9%
Edema limbs
9%
Hoarseness
9%
Dyspnea
9%
Weight loss
9%
Hypernatremia
9%
Thromboembolic event
9%
Creatinine increased
7%
Psychiatric disorders - Other, specify
7%
Anxiety
7%
Tremor
7%
Upper respiratory infection
7%
Pruritus
7%
Rash maculo-papular
6%
Memory impairment
6%
Proteinuria
6%
Mucositis oral
6%
Fever
6%
Hyperkalemia
6%
Hypertension
6%
Hypoglycemia
6%
Dysgeusia
6%
Dehydration
4%
Depression
4%
Urinary tract infection
4%
Arthralgia
4%
Generalized muscle weakness
4%
Fall
4%
Blurred vision
4%
Gastroesophageal reflux disease
4%
Confusion
4%
Diarrhea
4%
Muscle weakness right-sided
4%
Paresthesia
4%
Alkaline phosphatase increased
4%
Dry skin
4%
Muscle weakness left-sided
4%
Epistaxis
4%
Acute kidney injury
2%
Skin and subcutaneous tissue disorders-MACULAR ERRYTHEMATOUS, BACK AND ABDOMEN
2%
Hemorrhoids
2%
Flu like symptoms
2%
Myositis
2%
Pain in extremity
2%
Dysphasia
2%
Non-cardiac chest pain
2%
Cholecystitis
2%
Sore throat
2%
Alopecia
2%
Agitation
2%
Nasal congestion
2%
Cough
2%
Rash acneiform
2%
Conduction disorder
2%
Chills
2%
Abdominal pain
2%
Chest wall pain
2%
Hypersomnia
2%
Chest pain - cardiac
2%
Dyspepsia
2%
Gastrointestinal disorders - Other, specify: CHIPPED TOOTH
2%
Infections and infestations - Other, specify: H-PYLORI
2%
Papulopustular rash
2%
Radiation recall reaction (dermatologic)
2%
Myalgia
2%
Ataxia
2%
Cerebrospinal fluid leakage
2%
Peripheral sensory neuropathy
2%
Renal calculi
2%
Neck pain
2%
Edema cerebral
2%
Infections and infestations - Other, specify: SHINGLES
2%
Cognitive disturbance
2%
Muscle weakness lower limb
2%
Nervous system disorders - Other, specify: L HEMIPARESIS
2%
Nervous system disorders - Other, specify: LE WEAKNESS
2%
Allergic rhinitis
2%
Back pain
2%
Gastrointestinal disorders - Other, specify: GI BUG
2%
Pneumonitis
2%
Nervous system disorders - Other, specify: BASELINE L HEMIPARESIS
2%
Pulmonary edema
2%
Musculoskeletal and connective tissue disorder - Other, specify: CRAMPS IN FEET
2%
Weight gain
2%
Nervous system disorders - Other, specify: DECREASED GRIP STRENGTH IN R HAND
2%
Edema face
2%
Infections and infestations - Other, specify: LLE CELLULITIS
2%
Infections and infestations - Other, specify: LYME'S DX
2%
Urinary incontinence
100%
80%
60%
40%
20%
0%
Study treatment Arm
Naltrexone
Placebo

Trial Design

2Treatment groups
Experimental Treatment
Placebo Group
Group I: LDNExperimental Treatment1 Intervention
Naltrexone HCL, 4.5 mg, Once a day.
Group II: PlaceboPlacebo Group1 Intervention
Sugar pill
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
LDN
2011
Completed Phase 2
~110

Find a Location

Who is running the clinical trial?

Stanford UniversityLead Sponsor
2,474 Previous Clinical Trials
17,501,820 Total Patients Enrolled
Sean Mackey, MD, PhDPrincipal Investigator - Stanford University
Lucile Packard Children's Hospital Stanford, Stanford Hospital
University Of Arizona College Of Medicine (Medical School)
Tucson Hsps Medical Ed Prog Inc (Residency)
2 Previous Clinical Trials
563 Total Patients Enrolled
~6 spots leftby Jun 2025
Unbiased ResultsWe believe in providing patients with all the options.
Your Data Stays Your DataWe only share your information with the clinical trials you're trying to access.
Verified Trials OnlyAll of our trials are run by licensed doctors, researchers, and healthcare companies.
Back to top