Alterations in luteinizing hormones and testosterone levels following short-acting opioid ingestion are unknown but may assist in the diagnosis of hypogonadism in opioid consumers. Serial luteinizing hormones and testosterone values were measured every 2 hours for 10 hours following ingestion of either 0, 5, or 10 mg of hydrocodone on multiple isolated occasions, and demonstrated testosterone levels 2 and 4 hours after 10 mg ingestion to be 25% lower than those after 0 or 5 mg, with this difference resolving within 8 post-ingestion hours, indicating that knowledge of recent hydrocodone ingestion may be valuable in interpreting the significance of low morning testosterone levels in some patients.