Tetanus Antitoxin Dose for Prophylaxis
The recommended prophylactic dose of Tetanus Immune Globulin (TIG) for wound management is 250 units intramuscularly, administered as a single injection for wounds of average severity. 1, 2, 3
Standard Prophylactic Dosing
Administer 250 units IM as the standard prophylactic dose for tetanus-prone wounds in adults and children ≥7 years of age. 1, 2, 3
For children <7 years old, the dose may be calculated by body weight (4.0 units/kg), but it is advisable to administer the entire 250-unit dose regardless of the child's size, since theoretically the same amount of toxin will be produced regardless of body size. 3
When TIG and tetanus toxoid are given concurrently, use separate syringes and inject at separate anatomic sites to prevent interference with the immune response. 1, 2, 3
Clinical Algorithm for TIG Administration
TIG is indicated ONLY for patients with tetanus-prone wounds who have:
- Fewer than 3 documented doses of tetanus toxoid (incomplete primary series), OR 2, 3
- Unknown or uncertain vaccination history 2, 3
TIG is NOT needed for patients with:
- ≥3 documented doses of tetanus toxoid, regardless of time since last dose 2, 3
- Clean, minor wounds, even with incomplete vaccination history 3
Special Populations Requiring TIG
Immunocompromised patients (HIV infection, severe immunodeficiency) should receive TIG for contaminated wounds regardless of their tetanus immunization history. 4
If TIG supplies are limited, prioritize persons aged >60 years and immigrants from regions other than North America or Europe, as they are less likely to have adequate protective antibody levels. 2, 4
Treatment Dose for Established Tetanus
For established tetanus cases (not prophylaxis), administer 250-500 units IM immediately to neutralize circulating tetanospasmin that has not yet bound to neural tissue. 5
The dosage should be adjusted according to the severity of the infection. 3
Note that TIG cannot reverse damage already caused by toxin that has bound to the central nervous system, highlighting the critical importance of prompt administration. 5
Critical Pitfalls to Avoid
Do not confuse the 10-year routine booster interval with the 5-year interval for contaminated wounds—this is the most common error in tetanus prophylaxis. 4
Never delay TIG administration while awaiting laboratory confirmation—tetanus is a clinical diagnosis requiring immediate intervention. 5
Do not assume adequate immunity based on age or history alone—38% of tetanus cases occur in patients ≥65 years, and only 21% of women >70 years have protective antibody levels. 5
Avoid using equine antitoxin if human TIG is available, as equine products carry higher risk of allergic reactions (including anaphylaxis and serum sickness) and provide shorter duration of protection. 5, 6
Product Characteristics
Human TIG provides longer-lasting protection than animal-derived antitoxin and causes significantly fewer adverse reactions. 1
The case fatality rate for tetanus remains 18-21% even with modern intensive care, underscoring the importance of proper prophylaxis. 2, 5
Complete primary tetanus vaccination provides long-lasting protection ≥10 years for most recipients, making TIG unnecessary in fully vaccinated individuals. 1, 2