Who Should You Contact First if You Develop New Symptoms During a Clinical Trial?
If you have a medical emergency, such as severe difficulty breathing, sudden chest pain, loss of consciousness or inability to wake up, sudden confusion, or bleeding that will not stop, call the local emergency number or go to the nearest emergency department immediately. In mainland China, call 120; in other countries or regions, use the local emergency number. Do not wait for the study center to reply or for all your information to be ready before seeking care.[1][2]
Tell the healthcare staff treating you that you are taking part in a clinical trial, and show them your study contact card. You or someone accompanying you should notify the study team as soon as possible without delaying emergency care. Explain what happened even if you are unsure whether the symptoms are related to the study.[3][4]
Key points
- Promptly tell the study team about new or worsening symptoms, emergency department visits, and hospital admissions as required by the study. Report known side effects too. Start with the facts; you do not need to decide the cause yourself.[3][4]
- Before leaving the study center, save the daytime, after-hours, and backup contact details. Ask which situations require immediate contact and what to do if you cannot get through. Give the person accompanying you the local emergency care instructions and your study contact card.
- Decisions about stopping medication, the next dose, or emergency unblinding should be handled by the treating doctor and study doctor based on your condition and the study procedures. Do not delay necessary care to remain eligible for the trial.
What should you do first if you feel unwell now?
If it could be an emergency, seek emergency care nearby first. In addition to the situations listed in the opening paragraph, sudden inability to speak, sudden severe pain, or swelling of the face or tongue also require immediate help. Follow the guidance of local emergency dispatchers and the healthcare staff treating you about whether you need an ambulance and where to go. Do not delay care to return to the study hospital.[1][2]
If you have none of the emergency signs above but have new or worsening symptoms, promptly contact the study doctor or team as directed on your contact card or in the informed consent form. Describe your current symptoms and ask whether you need care now, where to go, and when to contact them again. If symptoms worsen or an emergency develops, use local emergency services directly.
If you cannot get through by phone, try the after-hours and backup numbers on the card. If you need prompt medical assessment or treatment, seek care nearby without waiting for a callback. Ask a family member to help make contact, and record when you called. Once you reach someone, ask them to confirm receipt of your report and agree on who will call back and when to make contact again. If you do not receive the agreed response, try again using the backup contact route.
What does the study team need to know?
Do not wait for all test results before making first contact. Start with the facts you know, mark anything unclear as “to be confirmed,” and provide updates later:[3][4]
- The study name or number, study center, and participant code; your current location and a callback number.
- What symptoms you have, when they started, whether they are improving or worsening, and how they affect eating, walking, or daily activities. If you have measurements, give the values and units.
- The date of your most recent study dose or procedure and whether your next dose is due soon; any recently added or changed medicines, over-the-counter medicines, and supplements.
- Whether you visited an emergency department or were admitted to hospital; the hospital and dates, tests and treatments already received, and the current doctor's plan. You can provide details you do not yet know later.
You could say:
I am taking part in [study name or number], and my participant code is [ ]. I started having [symptoms] at [time], and they are now [how they have changed]. My most recent study treatment was [date or “not sure”]. I am currently at [location/hospital], and my phone number is [ ]. Where should I go next, and who will call me back?
Report new symptoms, worsening of existing symptoms, abnormal test results, emergency department visits, and hospital admissions. Reactions already listed in the consent form must also be reported as required by the study. Even if you have no obvious symptoms, promptly tell the study team about missed doses, incorrect doses, or other medication errors as required by the study. The team may also require you to report pregnancy, device malfunctions, or other situations; ask about these when you enroll. You do not need to decide which type of safety report an event belongs to.[3][4]
How should care be coordinated after an emergency visit or admission to another hospital?
Show the treating doctor your study contact card, a list of known medicines, and the time of your most recent dose. If you do not know your assigned study group or the medicine's name, say so. Make sure the treating doctor knows how to contact the study doctor. Necessary care should begin first. If treatment requires knowing your blinded study assignment, ask the treating doctor to contact the study team and follow the study's emergency unblinding procedure. Do not wait for unblinding before seeking emergency care.
You or someone accompanying you should tell the study team as soon as possible which hospital you are in, your condition, and what treatment you have received. Keep emergency department records, test results, medication records, and discharge summaries, and send them to the study center through a secure channel approved by the hospital. Send new results as they become available. Ask which doctor will review the results, when the next contact will be, and how the local doctor and study doctor will communicate. Keep the documents in their original language; ask the recipient to confirm whether translation is needed.
If your next study treatment is due soon, ask the study doctor to give you specific instructions after considering the treating doctor's advice. If you cannot reach the study doctor and need prompt assessment or treatment, seek local care first and give the treating doctor your study documents. Do not change the dose or decide on your own whether to continue or pause study treatment.
The study team will assess the event and handle safety information under the applicable rules. Your report to the study team is a separate step from reports made by the research institution and sponsor to relevant parties; specific responsibilities vary by study type and applicable rules. Ask the team to explain who will notify you, when, and through which channel if new information becomes available that could affect your safety or willingness to continue, and whether your consent needs to be discussed again. Reporting symptoms does not by itself prove that the trial caused them, nor does it automatically mean you leave the study.[4][5]
Save this contact card on your phone and keep a paper copy
Ask the study center to fill in or check the details, and share them with the person accompanying you and your usual doctor:
| Item | Details to fill in |
|---|---|
| Study | Name and number; study center and hospital campus; participant code |
| Study team | Daytime phone number and service hours; after-hours or emergency number; backup number; available languages |
| Local emergency care | Local emergency number; location of the nearest emergency department; check again if you move |
| Treatment information | Known medicine or device name, date of the last dose/procedure; individual risk guidance provided by the team; mark anything unclear as unknown |
| Follow-up | Which symptoms require immediate contact; what to do if you cannot get through; when reporting is still required after stopping medication or leaving the study; how to send information securely |
Before leaving the study location or returning to your home country, check with the study center how to call from where you will be, the time difference, and available languages. Ask your doctor where you live to confirm whether they will accept the handover documents and who will review follow-up test results. Update the cards held by both sides if contact details change. If no after-hours number is available, ask the center to provide a clear written backup plan. In an emergency, contact local emergency services first.
Frequently asked questions
Should I report symptoms even if they seem mild?
Report new or worsening symptoms as required by the study, including reactions already listed. Ask the team which situations require immediate contact and which can be recorded and reported at an agreed time. Do not assume symptoms are unrelated.
What if I am not sure whether the study medicine caused my symptoms?
Simply describe honestly when they happened, how they changed, and any other known circumstances. The cause needs medical assessment; do not wait until you feel certain before reporting.[3][4]
Should I report symptoms that have already gone away?
Tell the study team when they started and resolved, and whether you received treatment. If you do not know the exact dates when reporting, give approximate times and explain what you are unsure about.
Can I still contact the center if symptoms develop after I stop the study medicine or leave the study?
Yes. Ask the team to explain your safety follow-up plan, how long you should stay in contact, and what you need to report. Stopping treatment, stopping study visits, and consenting to other follow-up should each be discussed separately. If you need emergency care, seek local care first.[5]
What if the local doctor does not know which trial I am in?
Show your contact card and available study documents, and ask the doctor to contact the study doctor. If you do not know the medicine's name or your assigned study group, say so. Do not delay assessment or treatment to gather missing information.
What about the costs of emergency care at another hospital and treatment for complications?
Seek care based on your condition first. Keep medical records, itemized bills, and receipts, and notify the study team as soon as possible. For studies covered by China's ethical review measures, research-related harm should receive prompt, free treatment, with compensation or damages handled under applicable provisions and agreements. Ask the center to explain how relatedness is assessed, how costs are handled, and how disputes are resolved.[6] Do not decide for yourself what caused the harm or who is responsible for paying. Before traveling, you can check each item against the cost guide.
Should I make contact if there is a pregnancy or a device problem but no symptoms?
Tell the study team as soon as possible as required by the study, describe the situation, and ask the team to explain the arrangements for further medical care and information collection. For a partner's or another person's personal medical information, first ask the team to explain how that person's consent will be obtained and how the information can be sent securely.
Sources
Date checked: November 6, 2026. Specific arrangements vary by study type, personal emergency plan, and location; confirm them with the study center.
- MedlinePlus: Recognizing medical emergencies (emergency warning signs in adults and children; the examples in this guide do not cover every situation).
- Shanghai Municipal Government: Emergency medical services; Emergency service numbers in China.
- US National Cancer Institute: Sample informed consent form (tell the study doctor about changes or new problems; this is an example, not the protocol for your study).
- China's Good Clinical Practice for Drug Trials (2026 revision) (adverse events, investigators' medical management, and safety reporting in drug trials; effective September 1, 2026).
- Measures for the Ethical Review of Life Science and Medical Research Involving Humans (participants' rights and withdrawal).
- National Health Commission: Full text of the ethical review measures (principles for treatment and compensation for research-related harm; the specific scope of application must be verified).