Neostigmine Methylsulfate: uses, dosing, side effects & brands
Neostigmine Methylsulfate is a cholinesterase inhibitor sold in the U.S. under 2 brand and generic names, for drug-induced abnormalities, urinary bladder diseases and myasthenia gravis. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Cholinesterase Inhibitor
- Treats
- Drug-Induced Abnormalities, Urinary Bladder Diseases and Myasthenia Gravis
- Available as
- Injectable
- Sold as
- 2 products — Neostigmine Methylsulfate and Bloxiverz
- Prescription?
- Prescription only
- Generic available?
- Yes
How neostigmine methylsulfate is dosed
From the FDA label for Neostigmine Methylsulfate (application ANDA212804). Other neostigmine methylsulfate products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Should be administered by trained healthcare providers. ( 2.1 ) Peripheral nerve stimulator and monitoring for twitch responses should be used to determine when neostigmine methylsulfate injection should be initiated and if additional doses are needed. ( 2.2 ) For reversal of NMBAs with shorter half-lives, when first twitch response is substantially greater than 10% of baseline, or when a second twitch is present: 0.03 mg/kg by intravenous route ( 2.2 ) For reversal of NMBAs with longer half-lives or when first twitch response is close to 10% of baseline: 0.07 mg/kg by intravenous route ( 2.2 ) Maximum total dosage is 0.07 mg/kg or up to a total of 5 mg (whichever is less). ( 2.2 ) An anticholinergic agent, e.g., atropine sulfate or glycopyrrolate, should be administered prior to or concomitantly with neostigmine methylsulfate injection. ( 2.4 ) 2.1 Important Dosage Information Neostigmine methylsulfate injection should be administered by trained healthcare providers familiar with the use, actions, characteristics, and complications of neuromuscular blocking agents (NMBA) and neuromuscular block reversal agents. Doses of neostigmine methylsulfate injection should be individualized, and a peripheral nerve stimulator should be used to determine the time of initiation of neostigmine methylsulfate injection and should be used to determine the need for additional doses. Neostigmine…
Neostigmine Methylsulfate side effects
Most common adverse reactions during treatment: bradycardia, nausea and vomiting. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Meitheal Pharmaceuticals Inc. at 1-844-824-8426 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adverse reactions to neostigmine methylsulfate are most often attributable to exaggerated pharmacological effects, in particular, at muscarinic receptor sites. The use of an anticholinergic agent, e.g., atropine sulfate or glycopyrrolate, may prevent or mitigate these reactions. Quantitative adverse event data are available from trials of neostigmine methylsulfate in which 200 adult patients were exposed to the product. The following table lists the adverse reactions that occurred with an overall frequency of 1% or greater. System Organ Class Adverse Reaction Cardiovascular Disorders bradycardia, hypotension, tachycardia/heart rate increase Gastrointestinal Disorders dry mouth, nausea, post-procedural nausea, vomiting General Disorders and Administration Site Conditions incision site complication, pharyngolaryngeal pain, procedural complication, procedural…
Who shouldn’t take neostigmine methylsulfate
Neostigmine methylsulfate is contraindicated in patients with: known hypersensitivity to neostigmine methylsulfate (known hypersensitivity reactions have included urticaria, angioedema, erythema multiforme, generalized rash, facial swelling, peripheral edema, pyrexia, flushing, hypotension, bronchospasm, bradycardia and anaphylaxis). peritonitis or mechanical obstruction of the intestinal or urinary tract. Hypersensitivity to neostigmine ( 4 ) Peritonitis or mechanical obstruction of the intestinal or urinary tract ( 4 )
Neostigmine Methylsulfate drug interactions
The pharmacokinetic interaction between neostigmine methylsulfate and other drugs has not been studied. Neostigmine methylsulfate is metabolized by microsomal enzymes in the liver. Use with caution when using neostigmine methylsulfate with other drugs which may alter the activity of metabolizing enzymes or transporters.
Every neostigmine methylsulfate product we track (2)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
| # | Drug | Rating | Type | Form | Generic? | Pharmacy pays | |
|---|---|---|---|---|---|---|---|
| 1 | 70/100 | Prescription | Injectable | No data | — | View → | |
| 2 | Not yet rated | Prescription | Injectable | No data | — | View → |
How long neostigmine methylsulfate keeps
No neostigmine methylsulfate label we read sets a separate limit for after opening, but they do specify how it must be stored — and the stability behind any date assumes those conditions.
Does neostigmine methylsulfate expire? The in-use limits and storage rules from its labelsWhat people report to the FDA about neostigmine methylsulfate
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 421 reports naming neostigmine methylsulfate, and the FDA flagged 89% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- hypotension29 reports
- nausea26 reports
- abdominal distension25 reports
- bradycardia20 reports
- respiratory failure20 reports
- abdominal pain19 reports
- white blood cell count increased18 reports
- generalised tonic-clonic seizure17 reports
Read these as a signal, not a rate. A report does not mean neostigmine methylsulfate caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
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Frequently asked questions
What is neostigmine methylsulfate?
Neostigmine Methylsulfate is a cholinesterase inhibitor used to treat Drug-Induced Abnormalities, Urinary Bladder Diseases, Myasthenia Gravis, Urinary Retention.
What kind of drug is neostigmine methylsulfate?
The FDA classifies neostigmine methylsulfate as a cholinesterase inhibitor. Cholinesterase inhibitors block the enzyme that breaks down acetylcholine, a chemical messenger nerves use to communicate. By letting acetylcholine build up and act longer, they can help preserve memory and thinking in Alzheimer's disease, where this messenger runs low. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take neostigmine methylsulfate with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run neostigmine methylsulfate against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What brand names is neostigmine methylsulfate sold under?
We track 2 neostigmine methylsulfate-containing products in the U.S.: Neostigmine Methylsulfate and Bloxiverz. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does neostigmine methylsulfate come in?
Across the brands we track, neostigmine methylsulfate is currently marketed as injectable, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic neostigmine methylsulfate?
Yes. Our catalog lists 1 generic neostigmine methylsulfate product alongside the brand versions. A generic has the same active ingredient and must meet the FDA's bioequivalence standard; it usually costs less. Ask your pharmacist which one your plan covers.
Cite this page
- APA
- pharmaranks. (2026, July 24). Neostigmine Methylsulfate: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/neostigmine-methylsulfate
- MLA
- “Neostigmine Methylsulfate: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/neostigmine-methylsulfate.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for neostigmine methylsulfate on DailyMed (NIH) ↗.