Can a Patient Take Pain Medications Before a HIDA Scan?
Opioid pain medications (narcotics) must be withheld for at least 48 hours before a HIDA scan, while acetaminophen (Tylenol) can be safely continued up to the time of the procedure. 1
Opioid Medications - Must Be Stopped
Opiate drugs should be discontinued at least 48 hours prior to HIDA scanning because they cause sphincter of Oddi spasm, which creates false-positive results by delaying or preventing gallbladder visualization and mimicking bile duct obstruction. 1
Why Opioids Interfere with HIDA Scans:
Opioids cause marked biliary sphincter spasm that delays clearance of the radiotracer from the common bile duct, simulating common bile duct obstruction in healthy individuals. 2
Morphine and other opioid metabolites circulate for many hours in the blood and directly decrease gallbladder ejection fraction by acting on the sphincter of Oddi, making accurate assessment of gallbladder function impossible. 3
Opioid-induced sphincter dysfunction can lead to erroneous diagnoses and potentially unnecessary surgical interventions, including common bile duct exploration. 2
Specific Opioids to Avoid:
The following medications must be withheld for at least 48 hours before testing: 1
- Morphine
- Hydrocodone (Vicodin, Norco)
- Oxycodone (Percocet, OxyContin)
- Codeine
- Hydromorphone (Dilaudid)
- Fentanyl
- Tramadol
- Meperidine (Demerol)
Acetaminophen (Tylenol) - Safe to Continue
Acetaminophen does not interfere with HIDA scan results and can be taken before the procedure. Acetaminophen is not listed among medications that affect gallbladder contraction or sphincter function. 1
Acetaminophen works through a different mechanism (central nervous system effects rather than opioid receptor binding) and does not cause sphincter of Oddi spasm. 4
Patients can continue acetaminophen for pain relief while preparing for their HIDA scan without compromising test accuracy.
Other Medications That Must Be Avoided:
Beyond opioids, the following medications should also be withheld for 24 hours before the scan because they affect gallbladder contraction: 1
- Anticholinergic drugs (48-hour hold)
- Nifedipine
- Indomethacin
- Octreotide
- Theophylline
- Benzodiazepines
- Phentolamine
- Isoproterenol
- Progesterone
- Nicotine and alcohol
Critical Clinical Pitfall:
A careful drug history, especially regarding opiate use, is essential before interpreting any HIDA scan with abnormal results. 3 Failure to obtain this history can lead to:
Misdiagnosis of sphincter of Oddi dysfunction in patients who have recently taken opiates (30% of suspected cases in one study were actually opiate-induced). 5
False-positive diagnoses of acute cholecystitis or bile duct obstruction. 2
Unnecessary endoscopic procedures or surgeries. 5
Alternative Pain Management Before HIDA Scan:
If pain control is needed in the 48 hours before a HIDA scan:
Use acetaminophen as the primary analgesic (safe to continue). 4
Avoid all opioid medications for at least 48 hours before the procedure. 1
If severe pain requires opioid analgesia and cannot be delayed, the HIDA scan should be rescheduled for at least 48 hours after the last opioid dose to ensure accurate results. 1, 3