A 28-year-old client is to receive penicillin G benzathine 1.2 million units IM for primary syphilis treatment. Which administration practice does the nurse implement?

Penicillin G benzathine (Bicillin L-A) is a long-acting depot intramuscular formulation used for primary, secondary, or early latent syphilis (single 2.4 million unit dose), late latent or unknown duration syphilis (2.4 million units weekly x 3), and rheumatic fever secondary prophylaxis (1.2 million units q3 to q4 weeks). Critical safety practices: (1) IM only — IV administration has been associated with cardiopulmonary arrest and death because of the suspension microcrystals; (2) deep IM into the ventrogluteal (preferred) or dorsogluteal in adults using a 21 to 23 gauge 1.5 to 2 inch needle with Z-track technique to reduce leak and pain; (3) for high doses, split between two sites; warm the syringe to room temperature, shake well, and use the diluent supplied; (4) post-injection monitoring for anaphylaxis for at least 30 minutes with epinephrine, oxygen, and resuscitation equipment available; (5) document allergy history thoroughly because penicillin G benzathine is contraindicated in true penicillin anaphylaxis and alternatives or desensitization are needed (e.g., for syphilis in pregnancy, desensitization is required because penicillin is the only adequate fetal treatment); (6) treatment of syphilis can trigger a Jarisch-Herxheimer reaction (fever, chills, myalgia within 24 hours); reassure and provide supportive care. IV push, SC, and immediate discharge are all unsafe.

IM only with Z-track and 30-minute monitoring. The IV-route warning is the most-tested NCLEX trap — Bicillin L-A must never be given IV.