What is the maximum dose of Rabishield (rabies monoclonal antibody) for a 20.8 kg child requiring post-exposure prophylaxis against rabies?

Maximum Dose of Rabishield for a 20.8 kg Child

For a 20.8 kg child requiring rabies post-exposure prophylaxis, administer 416 IU (approximately 2.8 mL) of Rabishield monoclonal antibody, calculated at 20 IU/kg body weight, infiltrated around and into the wound(s) if anatomically feasible, with any remaining volume given intramuscularly at a site distant from vaccine administration. 1

Dosing Calculation and Administration

• The standard dose for rabies immune globulin (whether polyclonal or monoclonal antibody) is 20 IU/kg body weight for all age groups, including children 2, 1

• For this 20.8 kg child: 20 IU/kg × 20.8 kg = 416 IU total dose 1

• This dose should be administered on day 0 (the day the first vaccine dose is given), ideally simultaneously with the first rabies vaccine dose 2, 3, 1

Critical Administration Guidelines

• Infiltrate the full calculated dose around and into the wound(s) if anatomically feasible, as this provides immediate passive immunity at the exposure site during the first 7-10 days before vaccine-induced antibodies develop 2, 3, 1

• Any remaining volume after wound infiltration should be administered intramuscularly in the deltoid muscle (for older children) or anterolateral thigh (for younger children) at a site distant from vaccine administration 2, 3, 1

• Never administer in the same syringe or at the same anatomical site as the vaccine, as this can interfere with vaccine efficacy 2, 3, 1

• Avoid the gluteal region for intramuscular administration due to risk of sciatic nerve injury 1

Timing Considerations

• If not administered on day 0, rabies immune globulin can still be given up to and including day 7 after the first vaccine dose 2, 3

• Beyond day 7, do not administer rabies immune globulin, as vaccine-induced antibody response is presumed to have occurred and additional passive antibody may suppress active antibody production 2, 3

Critical Dosing Pitfall to Avoid

• Do not exceed 20 IU/kg - higher doses can partially suppress active antibody production from the vaccine, potentially compromising protection 2, 3, 1

• The dose is the same whether using traditional human rabies immune globulin (HRIG) or newer monoclonal antibody products like Rabishield 1, 4

Vaccine Co-Administration

• This child should also receive the 4-dose rabies vaccine series (1.0 mL intramuscularly on days 0,3,7, and 14) in the deltoid or anterolateral thigh, at a different anatomical site from the immune globulin 2, 3

• If the child is immunocompromised, upgrade to a 5-dose vaccine regimen (days 0,3,7,14, and 28) with mandatory serologic testing after completion 2, 3