How many times can immunoglobulin be administered in a lifetime after a tick bite? - briefly
Immunoglobulin may be administered each time a clinically indicated tick‑bite exposure occurs, without a preset lifetime maximum; the number of courses is limited only by medical assessment of safety and necessity.
How many times can immunoglobulin be administered in a lifetime after a tick bite? - in detail
The passive antibody preparation used after a tick‑borne exposure is administered as a single course per incident. The standard regimen delivers 20 IU of immunoglobulin per kilogram of body weight, not to exceed 40 mL of product, and is given once at the time of the first medical evaluation.
If a person experiences a second tick bite that carries a risk of the same pathogen, the same protocol may be repeated after the new exposure, provided that the individual has not developed an allergic reaction to the previous dose. There is no formal lifetime ceiling imposed by regulatory agencies; the limiting factor is the clinical need for another prophylactic course.
Repeated administrations are constrained by the following considerations:
- Cumulative volume: each dose adds up to the maximum allowable infusion volume; excessive total volume may increase the risk of fluid overload.
- Immunogenicity: the likelihood of serum sickness or anaphylaxis rises with each exposure, especially if the product is not fully human‑derived.
- Cost and availability: immunoglobulin is a limited resource, and repeat courses are justified only when the benefit outweighs the expense.
In practice, most individuals will receive the preparation only once, because a single tick bite rarely warrants repeat prophylaxis. Should multiple exposures occur over a lifetime, each can be treated independently, but clinicians must assess the patient’s tolerance, total infused volume, and overall risk before authorising another administration.