USMLE High-Yield Questions on Instagram: "“tolerance kicked in but some things never change” ⸻ 📚 EXPLANATION (WITH ANSWER) Future’s been drinking lean for years, meaning chronic opioid use. With long-term opioid exposure, the body develops tolerance to many effects — but not all. Opioid effects that DO develop tolerance: • Euphoria • Analgesia • Respiratory depression • Sedation • Nausea Opioid effects that DO NOT develop tolerance: • Constipation → μ-receptor activation in the GI tract ↓ peris