In this episode, I’ll discuss the use of tetanus immune globulin.
Tetanus Immune Globulin can be part of successful tetanus post-exposure prophylaxis for certain patients as well as tetanus treatment.
In post-exposure prophylaxis scenarios, tetanus immune globulin provides immediate but temporary passive immunity to tetanus. The immunity is conferred because the tetanus immune globulin will bind and neutralize the free toxin that Clostridium tetani produces.
Peak concentrations are reached in 2 days and the half-life is 23 days.
Recommendations on who should receive tetanus immune globulin as post-exposure prophylaxis are those patients with less than 3 or an unknown number of tetanus vaccines and a dirty/contaminated wound.
Administration is IM only to the anterolateral aspects of the upper thigh or the deltoid muscle of the upper arm. Like all IM injections, gluteal administration is no longer recommended due to the risk of injury to the sciatic nerve.
If the patient is also receiving a tetanus vaccine, separate syringes and different anatomical sites must be used for each injection.
The IM dose for post-exposure prophylaxis in adults is 250 units.
When a patient develops clinical signs of tetanus, treatment consists of:
1. Supportive care and airway management
2. Neutralize any toxin that is not yet bound to nerve cells
3. Prevent toxin production
4. Control muscle spasms
5. Control autonomic instability
Tetanus immune globulin helps only with step #2 – it neutralizes remaining free toxin that is not yet bound irreversibly to nerve cells.
The dose of tetanus immune globulin for patients who develop tetanus is not as well-defined as those who need post-exposure prophylaxis. This is probably because the disease is too rare to effectively study comparative doses of tetanus immune globulin. Previous recommendations were for IM doses of 3000 to 6000 units. However CDC guidance for patients with tetanus is to use a lower dose of 500 units IM. The CDC states:
Researchers have not established the optimal therapeutic dose. However, experts recommend 500 international units (IU), which appears to be as effective as higher doses ranging from 3,000 to 6,000 IU and causes less discomfort.
The CDC also notes that while many experts recommend infiltration of the wound with tetanus immune globulin in patients who develop tetanus that this practice has not been shown to affect outcomes.
Members of my Hospital Pharmacy Academy have access to in-depth practical training from a pharmacist’s point of view on tetanus wound management, vaccination, and treatment, including the use of and alternatives to tetanus immune globulin. This is in addition to related training on the use of rabies vaccine and immune globulin, and over 140 other trainings in the areas of critical care, emergency medicine, infectious disease, and general hospital pharmacy. To browse the title and objectives of each training, follow the links at pharmacyjoe.com/training. To get immediate access the these and other resources to help in your practice, go to pharmacyjoe.com/academy.
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