First time

starting dosage for testosterone replacement therapy (TRT) is typically 100 mg per week (e.g., 0.5 mL of a 200 mg/mL solution) administered using a 1 mL syringe paired with a 23–25 gauge, 1 to 1.5-inch needle for intramuscular injections (or a 27–30 gauge needle for subcutaneous injections).