What is the recommended schedule for treatment with rabies immune globulin (RIG)?

Rabies Immune Globulin (RIG) Treatment Schedule

Rabies immune globulin should be administered only once at the beginning of post-exposure prophylaxis at a dose of 20 IU/kg body weight, with the full dose infiltrated around and into the wound(s) if anatomically feasible, and any remaining volume administered intramuscularly at a site distant from vaccine administration. 1

Dosing and Administration

• Administer 20 IU/kg body weight of rabies immune globulin, applicable to all age groups including children 2, 1
• RIG is administered only once at the beginning of post-exposure prophylaxis to provide immediate antibodies until the patient develops their own antibody response to the vaccine 2, 1
• If RIG was not administered when vaccination began, it can still be given through the seventh day after administration of the first dose of vaccine 2, 1
• Beyond the seventh day, RIG is not indicated since an antibody response to the vaccine is presumed to have occurred 1, 3

Administration Technique

• If anatomically feasible, the full dose of RIG should be thoroughly infiltrated in the area around and into the wounds 2, 1
• Any remaining volume should be injected intramuscularly at a site distant from vaccine administration 2, 1
• This infiltration recommendation is based on reports of rare failures of post-exposure prophylaxis when smaller amounts of RIG were infiltrated at exposure sites 2, 1
• RIG should never be administered in the same syringe or in the same anatomical site as vaccine 2, 1

Important Precautions

• Because RIG can partially suppress active production of antibody, no more than the recommended dose should be administered 2, 1
• Studies have shown that 40 IU/kg may interfere with optimal active antibody production, while 20 IU/kg shows minimal or no interference 4
• The combination of RIG and vaccine is recommended for both bite and nonbite exposures, regardless of the interval between exposure and initiation of treatment 2, 3

Complete Post-Exposure Prophylaxis Schedule

• For previously unvaccinated persons, RIG should be administered along with rabies vaccine 2
• Current vaccine schedule is 4 doses administered on days 0,3,7, and 14 2, 5
• For immunocompromised patients, a 5-dose schedule (days 0,3,7,14, and 28) is still recommended 2, 1
• Previously vaccinated persons require only vaccine (2 doses on days 0 and 3) and no RIG 2, 1

Safety Considerations

• Adverse reactions to RIG are rare, with studies showing only 0.183% of patients reporting transient mild adverse reactions 6
• The safety profile of human RIG is significantly better than older equine-derived products 2, 6
• Proper wound cleansing with soap and water and a virucidal agent (such as povidone-iodine) should always accompany RIG administration as part of comprehensive post-exposure prophylaxis 2, 3

Common Pitfalls to Avoid

• Failing to infiltrate the full dose of RIG around and into the wound(s) when anatomically feasible 2, 1
• Administering RIG in the same syringe or anatomical site as the vaccine 2, 1
• Exceeding the recommended dose of 20 IU/kg, which may suppress the immune response to the vaccine 2, 1, 4
• Delaying administration of RIG beyond 7 days after the first vaccine dose 2, 1
• Using alternative abbreviated vaccine schedules (like the 2-1-1 schedule) for severely exposed patients who also need RIG, as this may not provide adequate long-term protection 7