This page is general health information, not medical advice. It cannot tell you whether you have an infection. A clinician can, and the testing options on this site are a good place to start.

PEP stands for post-exposure prophylaxis. It is emergency HIV medication that a clinician prescribes after a possible exposure to HIV. The CDC says it must be started within 72 hours of the exposure to be considered.

If that window might still be open for you, the most useful step is to contact a clinic or an emergency department now. The rest of this guide can wait until you have made that call.

This guide explains how PEP HIV care works in Los Angeles, what to bring, what the steps look like, and what to expect afterward. It is written for people of every gender and orientation. Needing PEP is a medical situation, and clinicians handle it every day.

What PEP is, in plain words

PEP is a short course of HIV medicines. The CDC describes it as emergency medication for people who may have been exposed to HIV in the last 72 hours. A clinician decides whether it fits your situation. Only a clinician can prescribe it.

PEP is not the same as PrEP. PrEP is taken before possible exposures, as ongoing prevention. PEP is taken after a single possible exposure, as a time-limited course. Many clinics that offer one also offer the other.

The CDC says PEP can lower the chance of HIV taking hold when it is started promptly and taken as prescribed. It does not work every time, and no prevention method can promise that. That is one reason follow-up testing is part of the plan.

The 72-hour window

The CDC states that PEP should begin as soon as possible and no later than 72 hours after a possible exposure. Earlier is better. Every hour matters more than most people expect, so do not wait for a convenient time.

Count from the time of the possible exposure, not from when you started to worry about it. If you are not sure when it happened, say so. A clinician can work with an estimate.

If the 72 hours have already passed, you can still talk to a clinician. They can explain what the CDC guidance means for your situation and arrange HIV testing and other care. Do not assume it is too late without asking.

Materials: what to have ready

You do not need everything below to be seen. Do not delay going because you are missing something. Gather what you can in a few minutes:

A phone with a charge, so you can call and receive results messages.
Your best estimate of the date and time of the possible exposure.
A short, honest description of what happened. Clinicians ask in order to choose the right care, not to judge.
A list of medicines, supplements and allergies you have now.
Health insurance information, if you have it. The county clinics listed below do not charge patients.
A photo ID if you have one. The Los Angeles County Department of Public Health (DPH) says its clinics are open to everyone regardless of citizenship and that it will not report immigration status.
Someone you trust to come along or stay on the phone, if that would help.

Step-by-step: getting PEP in Los Angeles

Step 1. Note the time and act quickly

Write down when the possible exposure happened. Then work out when 72 hours will be up. Keep that time in front of you while you make the next calls.

If you are in immediate danger, or you were assaulted and need urgent medical care, call 911 or go straight to a hospital emergency department.

Step 2. Choose where to go based on the time of day

Clinic hours are limited, so the time of day decides your first stop.

Evenings, nights, weekends and holidays. A hospital emergency department is the option that is generally open at any hour. You can ask for evaluation for PEP after a possible HIV exposure. Staff may start you on medicine and refer you to a clinic for follow-up. Hospital policies differ, so call ahead if you can. This guide does not list a specific hospital, and the county's clinic pages do not either.

Daytime on clinic days. The clinics below list PEP among their services. Call first to confirm hours and how to be seen.

Step 3. Call or go to a clinic that offers PEP

These Los Angeles options are listed by LA County DPH and by the clinics themselves. Hours can change, so check before you travel.

Central Health Center (DPH Sexual Health Clinic), 241 Figueroa St., Los Angeles, CA 90012. DPH lists PEP, PrEP, DoxyPEP, HIV and STD testing and treatment here at no patient charge. Appointments are preferred, with limited walk-ins. The clinic is closed on Mondays.
MLK Jr. Center for Public Health (DPH Sexual Health Clinic), 11833 S. Wilmington Ave, Los Angeles, CA 90059. DPH lists the same full range of services, including PEP, with appointments preferred and limited walk-ins.
Los Angeles LGBT Center, McDonald/Wright Building, 1625 N. Schrader Blvd., Los Angeles, CA 90028. DPH lists walk-ins accepted and same-day appointments, Monday to Friday, 10am to 7pm. The Center lists PEP among its services. Its page does not state the cost of testing, so ask when you call. Phone: (323) 993-2997 per the DPH listing.
APLA Health, Gleicher/Chen Health Center Annex, 3741 S. La Brea Ave., Los Angeles, CA 90016, phone (213) 201-5000. APLA lists PEP and says its Out Here locations offer free or low-cost sexual health services. It directs patients to book an appointment, and its pages do not describe walk-in rules or sliding-scale fees.

For all DPH sexual health clinics, appointments go through one scheduling line: (213) 449-7009. DPH says telehealth visits are also offered by phone booking. Ask the scheduler to tell you that you are calling about PEP within 72 hours, so they can direct you correctly.

If you want help finding a place, the LA County PrEP and PEP warmline is (213) 351-7699, and DPH's GetPrEPLA site lists providers. The county HIV hotline is 800-367-2437 (800-367-AIDS). The CDC's tool at gettested.cdc.gov also lets you look up testing sites by ZIP code.

Step 4. Tell the clinician what happened

Share the timing, the type of possible exposure and any health conditions. The clinician will decide whether PEP is appropriate. They may also talk with you about other STIs, emergency contraception or pregnancy testing if those apply.

This is where honesty helps most. Nothing you describe is unusual to them.

Step 5. Have baseline tests

Before or when you start PEP, the CDC calls for an HIV test as a starting point. Clinicians also commonly check kidney function and test for other infections such as syphilis, gonorrhea and chlamydia. These results help the clinician pick a safe regimen.

Do not wait for results to start if the clinician says to begin. In an emergency, medicine usually starts the same day.

Step 6. Start the prescription and take it as directed

The CDC says PEP is taken for 28 days. The clinician decides which medicines you get and exactly how to take them. Follow their instructions rather than anything you read online. This guide does not give doses.

Ask before you leave:

What side effects are common, and which ones mean I should call you?
What should I do if I miss a dose?
Can I take this with my other medicines?
Who do I call if I run out or have a problem?

Step 7. Book your follow-up before you leave

PEP care includes return visits and more HIV testing after you start. The clinician will give you the dates. Ask for them in writing or in your patient portal. DPH says results from its clinics come through the LA Health Portal, usually in 2 to 10 business days.

Why follow-up testing matters

HIV tests cannot detect the virus right away. The CDC explains that a lab-based antigen/antibody blood test can usually detect HIV 18 to 45 days after an exposure. Other test types have different windows. The CDC lists some antibody tests as taking up to 90 days.

Because of this, one test on day one does not tell the whole story. A clinician will schedule tests at several points after your exposure. A result right after your exposure may not reflect an infection that is still too early to detect, so follow-up visits are part of the plan, not an extra.

Your clinician may also want to retest for syphilis, gonorrhea and chlamydia. If you want a longer list of places to get tested in the city, our guide to STD and HIV testing options in Los Angeles covers more clinics.

Tips for getting through the 28 days

Set a daily reminder. A phone alarm tied to a daily habit helps many people stay on schedule.
Take it the way the clinician said. Ask whether food matters for your prescription.
Call about side effects early. Nausea, tiredness and headache are commonly reported with HIV medicines. A clinician can often adjust the plan. Do not stop on your own.
Keep your other medicines and supplements on your list. Some can interact with PEP.
Use a backup plan for your supply. If a refill might fall on a weekend, ask about it ahead of time.
Ask about condoms and other protection. The clinician can explain how to protect partners while testing is still underway.

Common mistakes to avoid

Waiting until morning or Monday. The 72-hour window keeps running overnight and through weekends. Use an emergency department if clinics are closed.
Skipping the visit because of embarrassment. Clinicians see these situations often, and your care is confidential.
Stopping early because you feel fine. The CDC describes a full 28-day course. Talk to your clinician before changing anything.
Missing follow-up tests. The early tests cannot answer every question.
Using leftover or borrowed medicine. Only a clinician can prescribe PEP for your situation.
Assuming PEP replaces other prevention. It is a one-time emergency option, not a routine method.

What to expect afterward

When PEP is started promptly and taken as prescribed, the CDC says it can lower the chance of HIV infection. The medicine does not work in every case, and your follow-up tests are how you and your clinician will learn more over time.

Many people finish the course with only mild side effects, and some have none. Others have symptoms that need a medicine change. Both are normal reasons to call the clinic.

If a later test shows HIV, that is something a clinician can help with right away. HIV is not curable, but the CDC says it is treatable, and people who take HIV treatment as prescribed can stay healthy. Linking you to care is part of what these clinics do.

Many people also move on to PrEP afterward if they expect future exposures. DPH sexual health clinics provide PrEP, PEP and DoxyPEP at no patient charge. The California PrEP Assistance Program, run by the state health department's Office of AIDS, helps eligible residents pay for PrEP, including minors 12 to 17, regardless of immigration status. Ask a clinician or the program whether you qualify.

Questions people often ask

Can a teenager get PEP in Los Angeles?

Under California Family Code section 6926, as amended by AB 499 in 2011, a minor 12 or older may consent to STI testing and treatment. LA County DPH says its clinics tell patients 12 and older they can be tested and treated without their parents knowing. Ask the clinic how that applies to PEP when you call. Children's Hospital Los Angeles lists STD services for youth aged 12 to 24 at (323) 361-7550. It is best to call and confirm what they offer.

What does PEP cost?

DPH says patients are not charged at its sexual health clinics, and insurance is billed if you have it, with no copay or coinsurance. For other clinics, the cost is not published in the sources used here, so ask when you call.

How common is HIV in Los Angeles?

The LA County DPH 2025 HIV Snapshot reports 1,454 new HIV diagnoses among people 13 and older in Los Angeles County in 2024, a rate of 17 per 100,000. These figures are provisional. They show why prevention options like PEP and PrEP are widely available in the county, and they say nothing about any one person's risk.

Next steps: free and low-cost testing

After PEP, regular testing is the best way to keep track of your sexual health. The county's free hotline for finding testing is 800-758-0880. LA County DPH also runs a free mailed chlamydia and gonorrhea home test kit for people with a vagina aged 12 to 44 who live in the county. Information is on the DPH-run program site, la.dontthinkknow.org. The CDC's gettested.cdc.gov can help you find other nearby sites by ZIP code.

If you are weighing whether to go now, this is the short version. Call a clinic or go to an emergency department. Tell them the time. Ask about PEP. That one conversation can make the difference.

PEP in Los Angeles: Emergency HIV Prevention Within 72 Hours