Dexamethasone Injection and Gallamine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Dexamethasone Injection
Gallamine
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Decreased gallamine effectiveness; prolonged muscle weakness and myopathy
Interaction Deep Dive
In a number of case reports, the concomitant use of corticosteroids with neuromuscular blocking agents has been reported to antagonize neuromuscular blockade314. In addition, prolonged coadministration of these agents may increase the risk and/or severity of myopathy resulting in prolonged flaccid paralysis following discontinuation of the neuromuscular blocking agent 2.
Why it happens (mechanism)
Unknown
Literature reports
2 reports — tap to read
a) A 21-year-old male with idiopathic thrombocytopenic purpura was treated unsuccessfully with prednisone (100 to 250 mg daily) and was scheduled for splenectomy. Prior to the procedure the patient received pancuronium bromide 8 mg (0.1 mg/kg) and was intubated. One hour into the procedure, there was inadequate muscle relaxation. Even after four additional 2-mg doses, abdominal relaxation did not improve. The author speculated that the decreased effectiveness of the pancuronium was due to the high-dose corticosteroid therapy. The mechanism of the interaction may involve competition at the myoneural junction, alterations in protein binding, or induction of pancuronium metabolism 1.
b) A previously healthy 2-year-old burn patient was intubated and paralyzed with vecuronium (290 mg/kg; total dose 2433 mg) to allow artificial ventilation. In addition, the patient was given aminoglycosides and other antibiotics for sepsis. Dexamethasone 2.5 mg every six hours was administered intravenously for 18 days during the period of ventilation (45 days). When the vecuronium was discontinued, the patient showed no movement in any extremities other than trace finger movement. Muscle biopsy results were most consistent with a myopathy. Nearly eight months were required for the patient to recover sufficient muscle tone and strength 2.
Common questions
Can I take Dexamethasone Injection and Gallamine together?
Decreased gallamine effectiveness; prolonged muscle weakness and myopathy Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dexamethasone Injection and Gallamine interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Dexamethasone Injection or Gallamine need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there anything you'd monitor while I'm on both?
References (4)
- Laflin MJ: Interaction of pancuronium and corticosteroids. Anesthesiology 1977; 47:471-472. PubMed
- Gooch JL: AAEM case report number 29: prolonged paralysis after neuromuscular blockade. Muscle Nerve 1995; 18:937-942.
- Meyers EF: Partial recovery from pancuronium neuromuscular blockade following hydrocortisone administration. Anesthesiology 1977; 46:148-150. DOI
- Parr SM, Galletly DC, & Robinson BJ: Betamethasone-induced resistance to vecuronium: a potential problem in neurosurgery?. Anaesth Intensive Care 1991; 19:103-105. PubMed
Keep reading about Dexamethasone Injection
Keep reading about Gallamine
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
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