72-Hour PEP: HIV Prevention After A Potential HIV Exposure

1. What is PEP? How does it work?

PEP is a short course of antiretroviral (ARV) medication that stops HIV from taking hold in your body after a potential exposure. Once the virus enters, it needs time to multiply and attack the immune system. By starting PEP within the critical 72-hour window, the medication effectively blocks the virus from replicating, preventing a permanent HIV infection.

 👉 Read more: How Does PEP Work and How Effective Is It?

2. Who should use 72-Hour PEP?

• Individuals who have engaged in unprotected sex (anal or vaginal) or experienced condom break.
• Victims of rape or sexual assault
• Individuals who have shared needles/syringes with people who inject drugs, or shared tattooing, acupuncture, razor blades, or cosmetic tattooing equipment with someone suspected of having HIV. 
• Individuals whose compromised skin or mucous membranes (eyes, throat, nose) have been exposed to the blood or bodily fluids of an HIV-positive patient. 
• Individuals who have sustained needlestick injuries or cuts from sharp objects.

Note: PEP is only highly effective when initiated early, ideally within 2 hours and no later than 72 hours post-exposure. 

3. Consultation and Treatment Process at GD Health 

Risk Assessment 

Medical Experts will evaluate your HIV infection risk based on several factors, including the HIV status of your sexual partner, the type of sexual intercourse (vaginal, anal, or oral), and the protective measures used. They will also determine if you have any contraindications to PEP.

28-Day Treatment

Medical Experts will instruct you on how to administer the medication and how to manage potential side effects, what to do if you miss a dose. Some health issues may arise during the 28 days, therefore GD Health’s medical experts will offer continuous support and answer any inquiries you might have.

Post-Treatment HIV Screening

Based on the recommendations of the Centers for Disease Control and Prevention (CDC), PEP users are advised to undergo HIV testing at the following milestones: 

• Start of treatment
• 4 – 6 weeks
• 3 months
• 6 months

Note: Begin PEP treatment as soon as possible. Do not delay taking PEP because you cannot access an HIV test or are waiting for HIV test results. In addition to HIV, you should be tested for other sexually transmitted diseases (STDs) such as Syphilis, Hepatitis B, and Hepatitis C,…

 👉 Read more: DoxyPEP: The Dual Shield Protecting Your Health from Sexually Transmitted Diseases

4. Guidelines for Effective PEP Administration

When using 72h this medication, please adhere to the following instructions to ensure efficacy and safety during your treatment: 

• The golden period: Take the medication as soon as possible. Ideally, within the first 2 hours after exposure to the source of infection, and strictly no later than 72 hours. The earlier you start, the higher the efficacy. 
• Dosage: Take 1 pill per day for 28 days. 
• Strict Scheduling: You must take the pill consistently at the exact same time every day to maintain a stable drug concentration in your bloodstream. 
• Missed Doses: Take the missed dose as soon as you remember. However, if the time you remember is too close to your next scheduled dose (less than 4 hours), skip the missed dose and take the next dose at the regular time. Never take a double dose to make up for a missed one. 
• Prevention: Avoid unprotected sex, do not share needles, and prevent contact with others’ blood or bodily fluids to mitigate transmission risks. 
• Contact Medical Experts immediately: If you experience severe side effects or abnormal symptoms during the medication course. 

5. Side Effects of PEP Medication

Although PEP is clinically evaluated as safe, the combination of drugs in the regimen may cause several undesirable side effects: 

• Nausea: Commonly encountered when using medications such as Stavudine (d4T), Tenofovir (TDF), Zidovudine (ZDV), Didanosine (ddI), and Abacavir (ABC).
• Rash and Pruritus: Often associated with Lamivudine (3TC), ddI, ABC, etc. Mild cases can be managed with antihistamines; however, for severe manifestations such as Stevens-Johnson syndrome or Lyell’s syndrome, medication must be suspended and immediate hospitalization is required. 
• Headache and Dizziness: The most frequent side effect observed with PEP drugs like ZDV, 3TC, and Indinavir (IDV). This reaction typically occurs 1–2 hours post-administration and may persist until the following day. Headaches can be easily managed by taking Paracetamol. 
• Diarrhea: A quite common symptom in regimens containing Tenofovir (TDF), Saquinavir (SQV), or Lopinavir (LPV). Patients experiencing this should ensure adequate hydration and electrolyte replacement.
• Sleep Disturbances and Fatigue: May emerge during PEP therapy. This can be alleviated by utilizing dietary supplements that support sleep. 
• Hepatic Impairment: Drugs such as Nevirapine (NVP) or Zidovudine (ZDV) exhibit significant hepatotoxicity and can elevate liver enzymes, thus requiring cautious administration. 

If any of these side effects manifest, contact a GD Health Medical Expert immediately. 

6. Frequently Asked Questions (FAQ)

Nguyen Hung Manh, PharmD – A clinical pharmacist graduated from Hanoi University of Pharmacy and Duke University reviewed this content.

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