Hydrocortisone and Neostigmine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Hydrocortisone
Neostigmine
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 neostigmine effectiveness
Interaction Deep Dive
In several case reports of patients with myasthenia gravis maintained on anticholinesterases, the addition of corticosteroids resulted in a exacerbation of the patients' condition (after 48 hours)123.
Why it happens (mechanism)
Unknown
Common questions
Can I take Hydrocortisone and Neostigmine together?
Decreased neostigmine effectiveness Always confirm with your pharmacist or prescriber before making any change.
How serious is the Hydrocortisone and Neostigmine 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Hydrocortisone or Neostigmine 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 (3)
- Namba T: Corticotropin therapy in patients with myasthenia gravis. Electrophysiologic, pharmacologic studies. Arch Neurol 1972; 26:144-150. PubMed
- Brunner NG, Namba T, & Grob D: Corticosteroids in management of severe, generalized myasthenia gravis. Effectiveness and comparison with corticotropin therapy. Neurology 1972; 22:603-610. DOI
- Warmolts JR, Engel WK, & Whitaker JN: Alternate-day prednisone in a patient with myasthenia gravis. Lancet 1970; 2:1198-1199. DOI
Keep reading about Hydrocortisone
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:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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