Antirabies%252525252525252525252525252525252525252525252525252525252525252520vaccine

# Antirabies vaccine ## Overview Rabies vaccines are inactivated virus vaccines used for post-exposure prophylaxis (PEP) and pre-exposure prophylaxis (PrEP). Rabies vaccines available in the US include: * Rabies vaccine adsorbed (RVA) - Imogam® Rabies-FS is unavailable in the US. * Purified chick embryo cell (PCEC) vaccine - RabAvert® The choice of vaccine and specific PEP regimen may depend on availability and local public health guidelines. ## Primary Indications * Post-exposure prophylaxis (PEP) for individuals potentially exposed to rabies virus. * Pre-exposure prophylaxis (PrEP) for individuals at high risk of rabies exposure. ## Adult Dosing **Post-Exposure Prophylaxis (PEP):** * **For previously unvaccinated individuals:** * Intramuscular (IM): 1 mL of RVA or PCEC, administered on days 0, 3, 7, and 14. * Intradermal (ID): A 2-site ID injection of 0.1 mL (RVA) or 0.2 mL (PCEC) on days 0, 3, 7, and 14 for PrEP. A 1-site ID injection of 0.1 mL (RVA) or 0.2mL (PCEC) on days 0, 3, 7, 14, and 90 days for PrEP. _Note: ID administration of PEP is off-label in the US and requires specific training and protocols._ * **For individuals previously vaccinated (received a full primary series of rabies vaccine):** * IM: 1 mL of RVA or PCEC, administered on days 0 and 3. Rabies immune globulin (RIG) is NOT administered. * **For individuals with documented previous PEP (regardless of interval):** * IM: 1 mL of RVA or PCEC, administered on days 0 and 3. RIG is NOT administered. **Pre-Exposure Prophylaxis (PrEP):** * **Intramuscular (IM):** 1 mL of RVA or PCEC, administered on days 0, 7, and 21. * **Intradermal (ID):** _Off-label._ Standard WHO ID PrEP regimen: 0.1 mL (RVA) or 0.2 mL (PCEC) administered at 2 sites on days 0, 7, and 21 or 90. _Note: ID administration requires specific training and protocols._ ## Pediatric Dosing Dosing is weight-based for younger children when using vaccines that require it. **Post-Exposure Prophylaxis (PEP):** * **For previously unvaccinated individuals:** * IM: 1 mL of RVA or PCEC. Dosing is the same as adults. * ID: _Off-label. See adult section._ * **For individuals previously vaccinated:** Same as adult dosing. **Pre-Exposure Prophylaxis (PrEP):** * **Intramuscular (IM):** 1 mL of RVA or PCEC. Dosing is the same as adults. * **Intradermal (ID):** _Off-label. See adult section._ ## Dose Adjustments No dose adjustments are typically necessary for renal or hepatic impairment. ## Contraindications * Severe allergy to any component of the vaccine or prior severe reaction to rabies vaccine. ## Adverse Effects Common adverse effects include injection site reactions (pain, redness, swelling), headache, nausea, abdominal pain, muscle aches, and dizziness. Rare but serious adverse effects include anaphylaxis. Neurologic events are exceedingly rare. ## Key Drug Interactions * **Corticosteroids and other immunosuppressants:** May reduce the immune response to the vaccine. PEP is still recommended, but serologic testing may be considered to confirm adequate response. A booster dose may be necessary. * **Other vaccines:** Administer concurrently at different sites or according to schedule if not given concurrently. ## Monitoring * Local reactions at the injection site. * Signs and symptoms of systemic allergic reactions. * For PEP, assessment of the exposure event and animal is crucial for guiding management. * For immunocompromised individuals receiving PrEP or PEP, serologic testing (rabies virus neutralizing antibody titers) may be considered to confirm adequate immune response, typically 2-4 weeks after vaccination. Titers should be $\geq$ 0.5 IU/mL. ## Clinical Pearls * Rabies immune globulin (RIG) should be thoroughly infiltrated around the wound(s) and any remaining unused RIG should be administered IM at a site distant from vaccine administration. RIG is only given to unvaccinated individuals receiving PEP. * The decision to administer PEP should be made by public health officials or healthcare providers experienced in rabies prevention. * If a dog or cat has bitten someone, the animal should be observed for 10 days. If the animal remains healthy and has no signs of rabies during that period, PEP can be discontinued. * For wild animals (e.g., bats, raccoons, skunks, foxes), PEP is generally recommended unless the animal can be tested and found negative for rabies. * Consultation with local public health authorities is recommended for complex exposure scenarios. *** **Educational Disclaimer:** This information is intended for healthcare professionals and is not a substitute for professional medical advice. Always verify current prescribing information and consult with a qualified healthcare provider or public health official before making any treatment decisions. Dosing and recommendations may vary based on product labeling, local protocols, and individual patient factors.