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Showing 1–24 of 367 matching trials from the live ClinicalTrials.gov search.
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Completed Not applicable Interventional Accepts healthy volunteers

The Effect of Melatonin and Vitamin C on COVID-19

NCT04530539
Conditions
Covid19, SARS-CoV Infection
Interventions
Vitamin C, melatonin, Placebo, Symptom Survey
Dietary Supplement · Other
Lead sponsor
Lancaster General Hospital
Other
Eligibility
50 Years and older
Enrollment
122 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2022
U.S. locations
1
States / cities
Lancaster, Pennsylvania
Completed Not applicable Interventional Accepts healthy volunteers Results available

The Impact of Qualia Vitamin C+ on Blood Vitamin C Levels

NCT07285109
Conditions
Healthy, Suboptimal Vitamin C Levels
Interventions
Qualia Vitamin C+, Placebo
Dietary Supplement
Lead sponsor
Qualia Life Sciences
Industry
Eligibility
25 Years and older
Enrollment
36 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2025 – 2026
U.S. locations
1
States / cities
Carlsbad, California
Completed Phase 3 Interventional Accepts healthy volunteers Results available

Combined Antioxidant and Preeclampsia Prediction Studies (CAPPS)

NCT00135707
Conditions
Preeclampsia
Interventions
Dietary Supplement/Vitamins, Placebo for Vitamin C and Vitamin E
Drug
Lead sponsor
The George Washington University Biostatistics Center
Other
Eligibility
Female only
Enrollment
10,154 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2003 – 2009
U.S. locations
16
States / cities
Birmingham, Alabama • Chicago, Illinois • Detroit, Michigan + 13 more
Conditions
Femoral Fracture, Fragility Fracture, Muscle Atrophy
Interventions
Essential Amino Acid Supplementation
Combination Product
Lead sponsor
Michael C Willey
Other
Eligibility
65 Years and older
Enrollment
60 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2024 – 2026
U.S. locations
2
States / cities
Iowa City, Iowa • Eugene, Oregon
Completed Not applicable Interventional

Vitamin C and Cardiovascular Risk

NCT00534014
Conditions
Atherosclerosis, Type 2 Diabetes
Interventions
Vitamin C
Dietary Supplement
Lead sponsor
University of New Mexico
Other
Eligibility
18 Years to 75 Years
Enrollment
8 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2006 – 2007
U.S. locations
1
States / cities
Albuquerque, New Mexico
Conditions
Acne, Eczema, Skin Aging
Interventions
Hemptress Oil
Other
Lead sponsor
Hemptress
Industry
Eligibility
21 Years to 65 Years
Healthy volunteers
Accepts healthy volunteers
Timeline
2024
U.S. locations
1
States / cities
Santa Monica, California
Conditions
Vitamin C Deficiency, Smoking, Surgery, Surgery--Complications, Wound, Wound Complication, Wound Infection, Wound Dehiscence, Wound of Skin, Mandible Fracture, Mandible Open Fracture, Mandible Closed Fracture, Mandibular Fractures, Ascorbic Acid Deficiency, Oxidative Stress, Inflammation
Interventions
Vitamin C, Placebo
Dietary Supplement · Other
Lead sponsor
Hennepin Healthcare Research Institute
Other
Eligibility
18 Years and older
Enrollment
45 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2017 – 2021
U.S. locations
1
States / cities
Minneapolis, Minnesota
Recruiting Not applicable Interventional Accepts healthy volunteers

Developing a Nutritional Supplement to Increase Collagen Synthesis in People

NCT06138106
Conditions
Dietary Supplements, Connective Tissue, Exercise
Interventions
Natural Product Supplement, Placebo control
Dietary Supplement
Lead sponsor
University of California, Davis
Other
Eligibility
18 Years to 30 Years
Enrollment
20 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2023 – 2026
U.S. locations
1
States / cities
Davis, California
Conditions
Metastatic Pancreatic Cancer
Interventions
Ascorbic Acid, nab paclitaxel, Cisplatin, Gemcitabine
Drug
Lead sponsor
Piedmont Cancer Institute
Other
Eligibility
18 Years and older
Healthy volunteers
Healthy volunteers not accepted
Timeline
2019 – 2022
U.S. locations
3
States / cities
Atlanta, Georgia • Fayetteville, Georgia • Newnan, Georgia
Conditions
Asthma
Interventions
Fish Oil, Ascorbic Acid, Fish Oil Placebo, Ascorbic Acid Placebo
Dietary Supplement
Lead sponsor
Indiana University
Other
Eligibility
18 Years to 40 Years
Enrollment
14 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010
U.S. locations
1
States / cities
Bloomington, Indiana
Conditions
Essential Thrombocythemia, Polycythemia Vera, Primary Myelofibrosis
Interventions
Arsenic Trioxide, Ascorbic Acid, Laboratory Biomarker Analysis, Pharmacological Study
Drug · Dietary Supplement · Other
Lead sponsor
Roswell Park Cancer Institute
Other
Eligibility
19 Years and older
Enrollment
5 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2015
U.S. locations
1
States / cities
Buffalo, New York
Conditions
Effect of Food Supplement
Interventions
Placebo, Hydrolized Collagen, PrimaColl, Whey protein
Dietary Supplement
Lead sponsor
University of California, Davis
Other
Eligibility
18 Years to 30 Years
Enrollment
20 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2022 – 2024
U.S. locations
1
States / cities
Davis, California
Conditions
Reperfusion Injury
Interventions
Ascorbic Acid, 5 % Dextrose Water or Normal Saline
Drug · Other
Lead sponsor
Rutgers, The State University of New Jersey
Other
Eligibility
18 Years and older
Enrollment
57 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2007 – 2013
U.S. locations
1
States / cities
New Brunswick, New Jersey
Conditions
Burn
Interventions
Vitamin and Mineral supplementation
Dietary Supplement
Lead sponsor
Southern Illinois University
Other
Eligibility
19 Years and older
Enrollment
28 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2010 – 2011
U.S. locations
1
States / cities
Springfield, Illinois
Completed Not applicable Interventional Accepts healthy volunteers Results available

Cervical Preparation Before Dilation and Evacuation

NCT01751087
Conditions
Abortion, Induced
Interventions
Mifepristone, misoprostol, Osmotic dilators, placebo
Other · Drug · Device
Lead sponsor
Planned Parenthood League of Massachusetts
Other
Eligibility
18 Years and older · Female only
Enrollment
300 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2013 – 2014
U.S. locations
7
States / cities
San Francisco, California • Chicago, Illinois • Boston, Massachusetts + 3 more
Conditions
Renal Insufficiency, Chronic
Interventions
ISMN, Vitamin C
Drug · Dietary Supplement
Lead sponsor
University of Pennsylvania
Other
Eligibility
18 Years and older
Enrollment
8 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2016 – 2019
U.S. locations
1
States / cities
Philadelphia, Pennsylvania
Conditions
COVID-19, Coronavirus Infection, Sars-CoV2, Corona Virus Infection, COVID, Coronavirus, Coronavirus-19, Coronavirus 19
Interventions
Hydroxychloroquine, Vitamin C, Vitamin D, Zinc
Drug · Dietary Supplement
Lead sponsor
ProgenaBiome
Other
Eligibility
18 Years and older
Enrollment
254 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2020 – 2024
U.S. locations
1
States / cities
Ventura, California
Completed Not applicable Interventional Accepts healthy volunteers

Nutrition Interventions to Support the Immune System in Response to Stress

NCT02053506
Conditions
Mitigation of Immune Function Decrements in Response to Stress
Interventions
Immune-enhancing nutritional beverage, Probiotics (BB-12), Placebo (for nutritional beverage and probiotic)
Dietary Supplement
Lead sponsor
United States Army Research Institute of Environmental Medicine
Federal
Eligibility
18 Years to 45 Years
Enrollment
63 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2014 – 2016
U.S. locations
1
States / cities
Natick, Massachusetts
Conditions
Metastatic Pancreatic Cancer
Interventions
Gemcitabine and Erlotinib, Intravenous Vitamin C
Drug · Dietary Supplement
Lead sponsor
Sidney Kimmel Comprehensive Cancer Center at Thomas Jefferson University
Other
Eligibility
18 Years to 75 Years
Enrollment
14 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2009 – 2011
U.S. locations
1
States / cities
Philadelphia, Pennsylvania
Completed Phase 3 Interventional Results available

Vitamin C, Thiamine, and Steroids in Sepsis

NCT03509350
Conditions
Sepsis
Interventions
Vitamin C, Thiamine, Hydrocortisone, Vitamin C Placebo, Thiamine Placebo, Hydrocortisone Placebo
Drug
Lead sponsor
Emory University
Other
Eligibility
18 Years and older
Enrollment
501 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2020
U.S. locations
43
States / cities
Phoenix, Arizona • Tucson, Arizona • Los Angeles, California + 30 more
Completed Phase 3 Interventional Accepts healthy volunteers

Echinacea, Propolis and Vitamin C for URI Prevention in Preschoolers

NCT00231218
Conditions
Common Cold, Gastroenteritis
Interventions
dietary supplement--echinacea, propolis, and vitamin c
Drug
Lead sponsor
The Cleveland Clinic
Other
Eligibility
3 Years to 6 Years
Enrollment
104 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2006
U.S. locations
1
States / cities
Cleveland, Ohio
Conditions
Fontan Procedure, Hypoplastic Left Heart Syndrome, Tricuspid Atresia
Interventions
Vitamin C, Placebo
Dietary Supplement
Lead sponsor
University of Michigan
Other
Eligibility
8 Years to 25 Years
Enrollment
53 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2009 – 2010
U.S. locations
1
States / cities
Ann Arbor, Michigan
Active, not recruiting Not applicable Interventional Accepts healthy volunteers

Nitric Oxide Bioavailability and Early Life Stress (NO-Stress)

NCT02115724
Conditions
Cardiovascular Disease
Interventions
Antioxidant cocktail, Biopsy, Placebo, NMD; 0.4mg sub-lingual nitroglycerin spray
Dietary Supplement · Other · Drug
Lead sponsor
Augusta University
Other
Eligibility
18 Years to 40 Years
Enrollment
74 participants
Healthy volunteers
Accepts healthy volunteers
Timeline
2014 – 2027
U.S. locations
1
States / cities
Augusta, Georgia
Completed Not applicable Interventional Results available

Vitamin C Supplementation Intervention

NCT04036110
Conditions
Heart Failure
Interventions
Vitamin C 500 mg, Vitamin C 1000 mg, Placebo
Dietary Supplement · Other
Lead sponsor
University of North Carolina, Chapel Hill
Other
Eligibility
18 Years to 99 Years
Enrollment
36 participants
Healthy volunteers
Healthy volunteers not accepted
Timeline
2018 – 2020
U.S. locations
1
States / cities
Chapel Hill, North Carolina