Healthy volunteers · California
Studies for healthy volunteers in California
701 studies have at least one recruiting site in California. These studies say in their official record that they accept healthy volunteers. Many are Phase 1 studies that test how a new medicine is absorbed and tolerated; others recruit healthy people as a comparison group alongside patients.
701 recruiting studiesSource: ClinicalTrials.gov, refreshed October 26, 2026How we list studies
More recruiting studies (pay not posted)
- RecruitingHealthy volunteers
Engaging Mental Effort: Process- and Person-Based Reward Experiences, Effort Reinforcement Intervention, and Cascading Effects on Challenging Tasks
University of California, Davis
- Location
- Davis, CA
- Eligibility basics
- Ages 9–13
- RecruitingHealthy volunteers
Incentive Processing and Learning in Anorexia Nervosa and Bulimia Nervosa
University of California, San Diego
- Location
- La Jolla, CA
- Eligibility basics
- Ages 18–39 · Women only
- RecruitingHealthy volunteers
Fall Risk Assessment and Speech Intelligibility Enhancement Using In-ear Device
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 55+
- RecruitingHealthy volunteers
Effect of Ashwagandha Root Extract on Stress, Anxiety, and Sleep Quality in Adults Experiencing Minority Stress
SF Research Institute, Inc.
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–45
- RecruitingHealthy volunteers
Efficacy and Safety of Shatavari Root Extract in Women's Sexual Wellness
SF Research Institute, Inc.
- Location
- San Francisco, CA
- Eligibility basics
- Ages 20–50 · Women only
- RecruitingHealthy volunteers
Pregnancy and Developmental Outcomes After Transfer of Reportedly Aneuploid or Mosaic Embryos
Stanford University
- Location
- Sunnyvale, CA
- Eligibility basics
- Ages 18–55 · Women only
- RecruitingHealthy volunteers
Strain-Counterstrain Treatment of Piriformis Pain
Loma Linda University
- Location
- Loma Linda, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteersPhase 2
Examining Mu Opioid Mechanisms of Ketamine's Rapid Effects in OCD (MKET2)
Stanford University
- Location
- Stanford, CA
- Eligibility basics
- Ages 18–65
- RecruitingHealthy volunteers
Mechanistic Insights From Bronchoscopy Airway Samples
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–70
- RecruitingHealthy volunteers
Ketogenic Diet and Brain Response in Anorexia Nervosa
University of California, San Diego
- Location
- San Diego, CA
- Eligibility basics
- Ages 18–45
- RecruitingHealthy volunteersPhase 3
Local Bisphosphonate Effect on Recurrence Rate in Extremity Giant Cell Tumor of Bone
St. Louis University
- Location
- Los Angeles, CA + 10 other US sites
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Brief Behavioral Treatment for Insomnia in Veterans With Posttraumatic Stress Disorder
VA Office of Research and Development
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–75
- RecruitingHealthy volunteers
Hybrid Effectiveness-Implementation Trial of an Executive Functioning Intervention for Children's Mental Health Services
San Diego State University
- Location
- San Diego, CA + 1 other US site
- Eligibility basics
- Ages 6–99
- RecruitingHealthy volunteersPhase 4
Normal-weight Diabetes: Adipocyte-directed Therapy With Pioglitazone or Tirzepatide
Stanford University
- Location
- Palo Alto, CA
- Eligibility basics
- Ages 30–70
- RecruitingHealthy volunteers
Mediators and Moderators of Auditory Training
Northeastern University
- Location
- Riverside, CA + 2 other US sites
- Eligibility basics
- Ages 18–85
- RecruitingHealthy volunteersPhase 2
Sleep Health in U.S. Marines
San Diego State University
- Location
- San Diego, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Insomnia Treatment and Cardiometabolic Health in Older Adults With Posttraumatic Stress Disorder
University of California, Los Angeles
- Location
- North Hills, CA
- Eligibility basics
- Ages 50+
- RecruitingHealthy volunteers
Development, Attention, and Inhibition Study
University of California, Davis
- Location
- Davis, CA
- Eligibility basics
- Ages 4–7
- RecruitingHealthy volunteers
Comparing Hearing Aid Fitting Methods in Blast-exposed Veterans
VA Office of Research and Development
- Location
- Loma Linda, CA
- Eligibility basics
- Ages 18–60
- RecruitingHealthy volunteers
Role of Angiogenesis in Dermatologic Diseases: A Potential Therapeutic Target
University of California, Irvine
- Location
- Irvine, CA + 1 other US site
- Eligibility basics
- Ages 16+
- RecruitingHealthy volunteers
Collection of Blood for Multiple Collaborative Studies
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18+
- RecruitingHealthy volunteers
Early Intervention to Promote Cardiovascular Health of Mothers and Children
JHSPH Center for Clinical Trials
- Location
- San Luis Obispo, CA + 8 other US sites
- Eligibility basics
- Ages 18+ · Women only
- RecruitingHealthy volunteers
Prebiotic Effects of California Grapes on Gut Health and Cardiometabolic Health in Overweight Men and Women
University of California, Davis
- Location
- Davis, CA
- Eligibility basics
- Ages 45–70
- RecruitingHealthy volunteers
Optimizing Liver MRI Using Breath-Holding With and Without Oxygen
University of California, San Francisco
- Location
- San Francisco, CA
- Eligibility basics
- Ages 18–75
Who these studies look for
“Healthy” is decided at screening, not by you. Sites usually check vital signs, blood and urine tests, an ECG, your medications and sometimes your BMI or smoking status. A study can still turn you away for reasons that have nothing to do with being unwell, such as timing or a full roster.
Matching a page like this one never means you qualify. Each research team decides eligibility at screening.
Questions
Do healthy volunteer studies pay?
Many do, because volunteers give up time and follow strict schedules, but amounts are set by each study and are usually only confirmed by the research site. When a record states an amount we show the exact wording; otherwise we say compensation is not disclosed.
What happens at a screening visit?
Expect consent paperwork first, then a health questionnaire, vital signs, blood and urine samples and often an ECG. You can ask questions and withdraw at any time, before or after you sign.