Naltrexone is available in two forms: a 50 mg oral tablet and a 380 mg intramuscular (IM) injection. Healthcare professionals often prefer the IM injection because its effects last for one month, making it convenient for patients who may struggle with daily medication compliance. The dosing of naltrexone depends on the formulation. For the oral tablet, dosing can range between 25 and 100 mg, depending on the patient’s substance history and health. The IM injection is administered monthly in a fixed 380 mg dose.