Which antibiotic is primarily used for lifelong prophylaxis in sickle cell patients?

The primary antibiotic used for lifelong prophylaxis in sickle cell patients is Penicillin V. This is due to the increased susceptibility of these patients to infections, particularly from encapsulated organisms like Streptococcus pneumoniae. Sickle cell disease, characterized by impaired splenic function and increased risk of infections, necessitates routine penicillin prophylaxis starting in infancy and often continuing throughout life to mitigate this risk.

Penicillin V is effective at combating the specific bacteria that sickle cell patients are predisposed to, making it the appropriate choice for lifelong prophylaxis. While other antibiotics may have their own uses in various situations, they do not serve the same purpose in the context of preventing infections associated with sickle cell disease.