Antirabies%25252525252520vaccine

# Antirabies Vaccine ## Overview Rabies vaccine is an inactivated virus vaccine used for pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP). Two common formulations in the U.S. include Human Diploid Cell Vaccine (HDCV) and Purified Chick Embryo Cell Vaccine (PCECV). ## Primary Indications * **Pre-exposure prophylaxis:** Individuals at high risk for exposure (e.g., veterinarians, animal handlers, spelunkers, laboratory workers). * **Post-exposure prophylaxis:** Following contact with a suspected rabid animal, in conjunction with Rabies Immune Globulin (RIG) if indicated. ## Adult Dosing * **Pre-exposure:** 1 mL intramuscularly (IM) on days 0 and 7. * **Post-exposure (previously unvaccinated):** 1 mL IM on days 0, 3, 7, and 14. An additional dose on day 28 is required for immunocompromised patients. * **Post-exposure (previously vaccinated):** 1 mL IM on days 0 and 3. Do not administer RIG. ## Pediatric Dosing * **Dosing protocol is identical to adults.** Patients of all ages receive the same 1 mL IM volume. * **Site:** Preferred site for infants/toddlers is the anterolateral thigh; for older children and adults, the deltoid muscle is preferred. Never administer in the gluteal region. ## Dose Adjustments * **Immunocompromised patients (Post-exposure):** Must receive the 5-dose series (days 0, 3, 7, 14, and 28). Serologic testing 1–2 weeks after the last dose is recommended to confirm seroconversion. * *Note: Always consult local public health guidelines/CDC "Red Book" as protocols may shift based on exposure severity and patient immune status.* ## Contraindications * **Pre-exposure:** History of a severe allergic reaction (anaphylaxis) to a previous dose or any component of the vaccine. * **Post-exposure:** There are no contraindications to PEP, as rabies is universally fatal. If a serious allergic reaction occurs, seek specialist consultation and potentially consider alternative vaccine types or intensive management. ## Adverse Effects * **Local:** Pain, erythema, swelling, or pruritus at the injection site (common). * **Systemic:** Mild transient fever, headache, muscle aches, dizziness, or gastrointestinal symptoms. Serum sickness-like reactions occur rarely, typically with booster doses. ## Key Drug Interactions * **Immunosuppressants:** Corticosteroids, antimalarials (e.g., chloroquine), and chemotherapeutic agents may interfere with the development of an active immune response. Avoid or delay non-urgent vaccination; if required for PEP, verify seroconversion via antibody titers. * **Rabies Immune Globulin (RIG):** Administer RIG simultaneously with the first dose of the vaccine in PEP (infiltrated around the wound), but at a separate anatomical site. ## Monitoring * Monitor for signs of anaphylaxis for 15–30 minutes post-injection. * For immunocompromised patients, obtain rabies-neutralizing antibody titers 1–2 weeks after completing the PEP series. ## Clinical Pearls * **Route:** Always administer IM. Subcutaneous (SC) administration may result in lower antibody titers. * **Site:** Always use the deltoid in adults; use the anterolateral thigh in children <2 years or those with insufficient muscle mass. * **Storage:** Keep refrigerated (2°C to 8°C); do not freeze. Protect from light. * **Protocol Variations:** Always verify if local health departments or the CDC guidelines have specific modifications for unique animal exposure risks or circulating variants. *** **Educational Disclaimer:** This information is for educational purposes only. Rabies protocols are governed by state health departments and the CDC. Always verify specific dosing, eligibility, and current state-level public health recommendations via the [CDC Rabies Website](https://www.cdc.gov/rabies/) or your institutional infectious disease protocols before administration.