Clinical trials · California
Health clinical trials in California
We’re tracking 342 recruiting health studies with a site in California — including Phase 4 studies, each written for real people, not researchers.
Recruiting studies in California
- NCT07653776Recruiting
Study of wellness products for gut health
This study tests whether certain daily wellness products can improve gut-related quality of life. If you have room to feel better and are willing to take a product without knowing if it's active or a placebo, you may be able to join.
Del Mar, CaliforniaAges 21–105 - NCT07261254Recruiting
Baby Bonus: Support for families with newborns
This study tests if providing monthly payments and support to new parents can improve the health and well-being of their babies. If you live in San Mateo County and your baby is healthy and on Medicaid, you might be able to join.
Palo Alto, CaliforniaAges birth+ - NCT07713810Recruiting
Can supplements help with constipation? A study on health products
This study tests if certain health and wellness products can improve constipation and related health issues. It compares the active product to a placebo (a dummy product without active ingredients) to see if it really works.
Del Mar, CaliforniaAges 21–105 - NCT06842576Recruiting
Video to help teens get ready for adult healthcare
This study is testing a short video to help teens prepare for moving from pediatric to adult healthcare. It aims to see if the video makes teens feel more ready for this transition.
Los Angeles, CaliforniaAges 12–17 - NCT06525064Recruiting
Health-E You app study for teen guys
This study tests a health app designed for teen guys who have had vaginal or anal sex. It aims to see if the app can help with sexual health decisions and education.
Oakland, CaliforniaAges 13–21 - NCT05846282Recruiting
Student program to reduce mental health strain of resilience
This study is looking at ways to reduce the mental health and health burdens some students carry while trying to be “resilient.” It is for certain high school students in specific grades and backgrounds, to see if the program can help them feel better.
Los Angeles, CaliforniaAges 13 years+ - NCT06680700Recruiting
Testing a new health patch for oxygen levels
This trial tests a new patch that measures oxygen in your blood. Healthy volunteers wear the patch while their oxygen levels are briefly lowered in a controlled way to see how well the patch works.
Woodland Hills, CaliforniaAges 18–50 - NCT07546604Enrolling by invitation
Game-like app to prevent alcohol and mental health risks in women
This trial tests a smartphone app designed to help women prevent alcohol misuse and mental health problems. You play games in the app to build healthy habits.
Los Angeles, CaliforniaAges 18–69 - NCT05570734Recruiting
Study of diabetes support for Hispanic/Latino adults online
This study looks at an online (e-health) way to help adults with type 2 diabetes better follow their diabetes care plan. It targets Hispanic/Latino patients and may help improve how consistently people manage their diabetes.
Chula Vista, CaliforniaAges 18 years+ - NCT07421596Recruiting
Dietary supplement study for gut and digestive health
This trial tests whether a dietary supplement system can improve gut and digestive health over 8 weeks. You may be eligible if you have digestive symptoms like bloating, stomach pain, or diarrhea.
San Francisco, CaliforniaAges 18–80 - NCT07339228Enrolling by invitation
Youth soccer and mental health study
This trial combines soccer with behavioral health support to help young people ages 14–21. It tests if joining team sports and group activities improves mental well-being.
Oakland, CaliforniaAges 14–21 - NCT07215689Recruiting
Ashwagandha for healthier skin and hair
This trial tests a daily 300 mg ashwagandha supplement (KSM-66) to see if it improves skin and hair health over three months. It is for generally healthy adults experiencing mild to moderate hair loss.
San Francisco, CaliforniaAges 18–60 - NCT06897982Recruiting
Nutrition program for prediabetes at health center
This study tests a nutrition program for people with prediabetes at a health center. It aims to see if the program is practical and can help prevent type 2 diabetes.
Los Angeles, CaliforniaAges 18–99 - NCT06230367Recruiting
Text program for HIV prevention for young guys who like guys
This trial tests a text-messaging program to help young guys who have sex with guys stay HIV-negative. It's designed for teens and young adults who own a cell phone and can take a quick HIV test at home.
San Clemente, CaliforniaAges 13–22 - NCT05984589Recruiting
Personal health coaching for colorectal cancer survivors
This study tests a personalized health coaching program to help colorectal cancer survivors improve their lifestyle habits, such as diet and physical activity, which may improve their health and well-being.
Los Angeles, CaliforniaAges 18 years+ - NCT05589155Recruiting
Using a phone app to improve blood sugar and weight
This study looks at whether a mobile phone app can help people with type 2 diabetes improve their health habits, including blood sugar monitoring and weight. You may be able to join if you already check your blood sugar daily and are able to use a smartphone.
San Diego, CaliforniaAges 18–64 - NCT04855773Recruiting
Mobile text-message support to help people stay on PrEP
This trial tests whether phone-based (iPhone/Android) text-message support can improve how consistently people use PrEP, an HIV prevention medicine. It may help you stay on track with refills and clinic visits, especially if you’re at higher risk of stopping PrEP.
San Francisco, CaliforniaAges 15 years+ - NCT07735221Recruiting
Peanuts for stress and heart health
This trial tests whether eating peanuts every day can reduce stress, improve immune function, and lower inflammation in people who feel stressed. If you are stressed and generally healthy, you may qualify.
Davis, CaliforniaAges 18–65 - NCT07713264Recruiting
Outdoor workers' safety study in California
This study listens to outdoor workers and community members in three California counties to understand safety needs. Participants will use a smartphone app or a provided phone to share what they see in their community.
Stanford, CaliforniaAges 18 years+ - NCT07686614Enrolling by invitation
Phone support for parents of young children
This study provides phone-based support to parents or guardians of children under 12 who have experienced difficult or stressful situations. The goal is to help families connect with services that can support the child's well-being.
Pasadena, CaliforniaAges Any age - NCT07671989RecruitingPhase 4
Period pills for late period: a new option
This trial tests if a two-pill combination can safely bring on a late period. It is for people who do not want to be pregnant and understand the pills will end a pregnancy if one exists.
Oakland, CaliforniaAges 18 years+ - NCT07602374Recruiting
Written vs. Video Education for Breast Reconstruction Surgery
This study compares two ways of learning about breast reconstruction options after mastectomy—reading written materials versus watching videos. Researchers want to see which method helps patients make better-informed decisions and feel more confident about their choice.
San Francisco, CaliforniaAges 18 years+ - NCT07591584Recruiting
Digestive Enzyme Blend for Bloating and Gas Relief
This study tests whether a daily digestive enzyme supplement designed to break down certain hard-to-digest foods can reduce bloating and belly pain. You'll use a smartphone app to track your symptoms over several weeks to see if the enzyme helps.
Los Angeles, CaliforniaAges 18 years+ - NCT07557303Recruiting
Understanding Prenatal Screening Decisions During Pregnancy
This study helps pregnant people make informed choices about genetic screening tests by providing clear, timely information. Researchers want to learn the best way to explain screening options so you can decide what's right for you and your family.
San Francisco, CaliforniaAges 18 years+
Where these studies are running in California
Institutions with a site for the recruiting health studies listed above.
- Cedars-Sinai Medical Center · 2 studies
- Radicle Science Inc. · 2 studies
- San Francisco Research Institute · 2 studies
- Bridge HIV, San Francisco Department of Public Health
- Center for Innovative Public Health Research
- Children Hospital Los Angeles
- Kaiser Permanente School of Medicine
- Loyola Marymount University
What taking part in a health study involves
A screening visit first
Before anything else, the study team checks whether you fit — usually a visit with some tests. You can stop at any point, and screening is typically free.
Care at a nearby site
Study visits happen at a clinic or hospital taking part. Many studies cover the cost of the study treatment and related visits, and some reimburse travel.
You stay in control
Taking part is voluntary and you can leave a study at any time, for any reason, without affecting your regular care.
The team decides eligibility
Our fit check is a helpful first read, not a decision. The study team makes the final call after reviewing your health history.
Common questions
- Are there health clinical trials in California?
- Yes. We're currently tracking 342 recruiting health studies with a site in California, each rewritten in plain language so you can see what it's testing and who it's for.
- How do I find out if I qualify for a health study in California?
- Each study lists its eligibility rules — age, diagnosis, prior treatments. On every trial page we explain these in plain language and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Do I have to live in California to take part?
- Not necessarily. These studies have a site in California, but eligibility is about your health, not your address — some people travel to take part, and a few studies reimburse travel. The study team can tell you what's required.
- Does it cost anything to join a health trial?
- Using Clin2 is always free. Many trials cover the study treatment and related visits; some reimburse travel. The study team explains exactly what's covered before you decide.
Not the right time?
New health studies open in California regularly. Set up a health profile and we’ll quietly watch for studies that fit you and email you when one opens.
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. Talk with your doctor about whether a specific trial is right for you.