Antirabies%252525252525252525252525252525252525252525252525252520vaccine

# Antirabies Vaccine ## Overview Rabies vaccines are inactivated vaccines that provide passive immunity against the rabies virus. They are used for pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP). ## Primary Indications * **Pre-exposure prophylaxis (PrEP):** For individuals at high risk of exposure to rabies virus (e.g., veterinarians, animal handlers, travelers to rabies-endemic areas). * **Post-exposure prophylaxis (PEP):** For individuals following potential rabies virus exposure. ## Adult Dosing * **PrEP:** * Intramuscular (IM): 1 mL on days 0, 7, and either day 21 or 28. * Intradermal (ID): 0.1 mL on days 0, 7, and either day 21 or 28 (often used in resource-limited settings, efficacy may be slightly lower than IM). * **PEP:** * **For previously unvaccinated individuals:** * Rabies Immune Globulin (RIG): 20 International Units (IU)/kg body weight, given IM once, infiltrated around the wound site as much as possible. If anatomically feasible, the remainder of the dose should be given IM at a site distant from vaccine administration. * Rabies Vaccine: 1 mL IM on days 0, 3, 7, and 14 (4 doses total). * **For previously vaccinated individuals (completed full series):** * Rabies Immune Globulin (RIG): Not recommended. * Rabies Vaccine: 1 mL IM on days 0 and 3 (2 doses total). ## Pediatric Dosing Pediatric dosing is typically weight-based for RIG, but the volume of vaccine administered is usually the same as for adults. * **PrEP:** Same schedule as adults (1 mL IM or 0.1 mL ID). * **PEP:** * **For previously unvaccinated children:** * RIG: 20 IU/kg body weight, given IM. * Rabies Vaccine: 1 mL IM on days 0, 3, 7, and 14. * **For previously vaccinated children:** * RIG: Not recommended. * Rabies Vaccine: 1 mL IM on days 0 and 3. ## Dose Adjustments No specific dose adjustments are generally required for hepatic or renal impairment. Dosing is primarily determined by exposure history and vaccination status. ## Contraindications * Severe allergic reaction (anaphylaxis) to a previous dose of rabies vaccine or any component of the vaccine. * Severe acute illness (vaccination should be postponed until recovery). ## Adverse Effects * **Local:** Pain, redness, swelling, itching at the injection site. * **Systemic:** Headache, fatigue, muscle aches, nausea, dizziness, low-grade fever. * Rarely: Neurologic events (very rare, causal link often unclear). ## Key Drug Interactions * **Corticosteroids and other immunosuppressants:** May reduce the immune response to the vaccine. If concurrent use is necessary, assess antibody titers and consider additional doses. * **Antimalarials (e.g., chloroquine):** May interfere with the immune response to intradermal vaccine administration. If possible, administer IM or avoid concurrent use. ## Monitoring * Monitor for potential adverse reactions. * For individuals receiving PEP, ensure completion of the vaccine series and RIG administration (if indicated). * For PrEP, consider antibody titer testing every 2 years for persons with ongoing significant risk of exposure, or based on local protocol. ## Clinical Pearls * RIG should be administered at the time of the first vaccine dose (day 0) and infiltrated around the wound site as much as possible. * PEP is recommended for *all* bites and scratches from potentially rabid animals, even if the animal appears healthy, unless the animal can be observed for 10 days and is found to be healthy. * The decision to administer PEP should be made on a case-by-case basis, considering the species of the animal, the circumstances of the exposure, the availability of the animal for testing, and the prevalence of rabies in the geographic area. * Combination vaccines (e.g., Purified Chick Embryo Cell vaccine) are generally preferred for PEP. **Educational Disclaimer:** This information is intended for healthcare professionals. Always consult the official prescribing information and relevant guidelines for the most current and comprehensive drug information, as recommendations and product availability may vary.