Rabies Vaccine

• Pre-exposure Prophylaxis (PrEP):
• Individuals at high risk for rabies exposure, including veterinarians, animal handlers, laboratory personnel working with the rabies virus, and travelers to endemic areas.
• Post-exposure Prophylaxis (PEP):
• Following suspected or confirmed exposure to rabies virus through bites, scratches, or contact of mucous membranes with saliva of potentially rabid animals.
• Administered in combination with rabies immunoglobulin (RIG) for individuals not previously vaccinated.
• Off-label/Clinically Accepted Uses:
• Use in immunocompromised patients with adjusted regimens.
• Use for wild animal exposures in endemic regions.

Pre-exposure Prophylaxis (PrEP):

• Adults and children ≥1 year:
• Three doses of 1 mL intramuscularly (IM) or intradermally (ID) on Days 0, 7, and 21 or 28.
• Booster doses recommended every 2–3 years for those continuing at risk.

Post-exposure Prophylaxis (PEP):

• Unvaccinated individuals:
• Four doses of 1 mL IM on Days 0, 3, 7, and 14.
• Rabies immunoglobulin (RIG) administered on Day 0 infiltrated around wounds.
• Previously vaccinated individuals:
• Two doses of 1 mL IM on Days 0 and 3.
• RIG is not administered.

Route:

• Intramuscular injection preferably in the deltoid muscle (avoid gluteal injection).
• Intradermal administration is accepted in some countries following specific protocols.

Special Populations:

• Pediatrics: Same dosing as adults (adjusted by weight for IM injections).
• Elderly: No dose adjustment required.
• Immunocompromised: May require additional doses or antibody titer monitoring.

Rabies vaccine contains inactivated rabies virus antigens that stimulate the immune system to produce virus-specific neutralizing antibodies. These antibodies prevent rabies virus entry into the nervous system by binding to viral glycoproteins, thereby neutralizing the virus. The vaccine also induces cellular immunity and immunologic memory, providing long-term protection against rabies infection upon subsequent exposures.

• Absorption: Rapid absorption after IM or ID injection.
• Distribution: Vaccine antigens are processed by immune cells at the injection site and lymph nodes.
• Metabolism: Antigens are broken down by antigen-presenting cells; not metabolized via traditional drug pathways.
• Elimination: Degraded by the immune system; no renal or hepatic clearance.
• Onset of Immunity: Neutralizing antibodies typically develop within 7–14 days after initial vaccination.
• Duration of Immunity: Protective antibody titers persist for several years, depending on risk exposure and booster administration.

• Pregnancy:
• No evidence of harm from available data; animal studies show no teratogenicity.
• Vaccination is recommended during pregnancy if there is a risk of rabies exposure.
• Lactation:
• Considered safe; no known adverse effects in breastfeeding infants.

• Active Immunizing Agent
• Inactivated Viral Vaccine

• Known hypersensitivity to rabies vaccine components or previous severe allergic reaction to rabies vaccine.
• Moderate or severe acute illness (vaccination should be deferred until recovery).

• Observe patients for hypersensitivity or anaphylactic reactions after vaccination.
• Immunocompromised individuals may exhibit reduced immune response; monitor antibody titers as necessary.
• Avoid gluteal muscle injections due to potential reduced vaccine efficacy.
• Ensure timely and complete vaccination series for effective prophylaxis.
• Administer RIG promptly in unvaccinated individuals with category III exposures.

Common:

• Injection site pain, redness, swelling.
• Mild systemic symptoms: fever, headache, fatigue, nausea.

Serious (rare):

• Hypersensitivity reactions including anaphylaxis.
• Neurological events such as Guillain-Barré syndrome (extremely rare).

• Immunosuppressive medications may decrease vaccine efficacy.
• Concurrent administration of rabies immunoglobulin (RIG) with vaccine is recommended for PEP in unvaccinated patients but given at a different anatomical site.
• No significant CYP450 or drug-food interactions reported.

• WHO and CDC recommend a 4-dose vaccine regimen for PEP in unvaccinated patients.
• Intradermal vaccination protocols are endorsed in resource-limited settings to reduce costs.
• Emphasis on early wound cleaning and timely initiation of vaccine and RIG.
• Avoid gluteal administration due to inconsistent immune response.

• Store refrigerated at 2°C to 8°C (36°F to 46°F).
• Protect from light.
• Do not freeze.
• Use vaccine immediately after reconstitution or store according to manufacturer instructions (usually stable for up to 8 hours at 2–8°C).