Atropine: uses, dosing, side effects & brands
Atropine is an anticholinergic sold in the U.S. under 3 brand and generic names, for bradycardia, heart arrest and poisoning. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Anticholinergic
- Treats (across its forms)
- Bradycardia, Heart Arrest and Poisoning
- Available as
- Injectable · Solution
- Sold as
- 3 products — Atropen, Atropine Sulfate and Isopto Atropine
- Prescription?
- Prescription only
- Generic available?
- Yes
- What the pharmacy pays
- about $7 per ml — not your price
How Atropen is dosed
From the FDA label for Atropen (application NDA017106). Other atropine products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
ATROPEN is a single-dose autoinjector intended as an initial treatment of the muscarinic symptoms of insecticide or nerve agent poisonings; definitive medical care should be sought immediately. ( 2.1 ) Dosage is dependent on weight. ( 2.2 ) Dosage for Mild Symptoms: If the patient experiences two or more mild symptoms, administer one injection intramuscularly into the mid-lateral thigh. If, at any time after the first dose, the patient develops any of the severe symptoms, administer two additional injections intramuscularly in rapid succession. ( 2.2 ) Dosage for Severe Symptoms: If the patient is either unconscious or has any of the severe symptoms, immediately administer three injections intramuscularly into the patient's mid-lateral thigh in rapid succession. ( 2.2 ) 2.1 Important Administration Information It is recommended that three ATROPEN autoinjectors be available for use in each patient at risk for organophosphorus or carbamate poisoning; one (1) for mild symptoms plus two (2) more for severe symptoms [see Dosage and Administration ( 2.2 )] . Different dose strengths of ATROPEN are available depending on the patient's weight. ATROPEN should be used by persons who have had adequate training in the recognition and treatment of nerve agent or insecticide intoxication, but may be administered by a caregiver or self-administration if a trained provider is not available.…
Everything below is the FDA label for Atropen (injectable). Atropine is also sold as solution, and those are different medicines to take — follow the label for the one you were prescribed.
Atropen side effects
The following serious adverse reactions are described elsewhere in the labeling: Cardiovascular Risks [see Warnings and Precautions ( 5.1 )] Heat Injury [see Warnings and Precautions ( 5.2 )] Acute Glaucoma [see Warnings and Precautions ( 5.3 )] Urinary Retention [see Warnings and Precautions ( 5.4 )] Pyloric Stenosis [see Warnings and Precautions ( 5.5 )] Exacerbation of Chronic Lung Disease [see Warnings and Precautions ( 5.6 )] Hypersensitivity [see Warnings and Precautions ( 5.7 )] The following adverse reactions associated with the use of atropine were identified in the literature. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Mild to moderate pain may be experienced at the site of injection. Common adverse reactions of atropine include dryness of mouth, blurred vision, dry eyes, photophobia, confusion, headache, dizziness, tachycardia, palpitations, flushing, urinary hesitance or retention, constipation, abdominal pain, abdominal distention, nausea, vomiting, loss of libido, and impotency. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Meridian Medical Technologies ® , LLC at 1-833-739-0945 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. Adverse Reactions at Recommended Doses Common adverse reactions of…
Who shouldn’t take Atropen
None. None.
Atropen drug interactions
Pralidoxime: The signs of atropinization (flushing, mydriasis, tachycardia, dryness of the mouth and nose) may occur earlier than might be expected than when atropine is used alone. ( 7.1 ) Barbiturates: Atropine may potentiate the effect of barbiturates. ( 7.2 ) 7.1 Pralidoxime When atropine and pralidoxime are used together, the signs of atropinization (flushing, mydriasis, tachycardia, dryness of the mouth and nose) may occur earlier than might be expected when atropine is used alone because pralidoxime may potentiate the effect of atropine. Excitement and manic behavior immediately following recovery of consciousness have been reported in several cases. However, similar behavior has occurred in cases of organophosphate poisoning that were not treated with pralidoxime. 7.2 Barbiturates Barbiturates are potentiated by the anticholinesterases; therefore, barbiturates should be used cautiously in the treatment of convulsions resulting from exposure to atropine.
Every atropine product we track (3)
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 | Not yet rated | Prescription | Injectable | Generic | $7 | View → | |
| 2 | Not yet rated | Prescription | Injectable | Generic | $7 | View → | |
| 3 | Not yet rated | Prescription | Solution | Generic | $7 | View → |
Combination products containing atropine
A combination is a different drug — different dosing, different warnings. It is listed here so you can find it, not so you can substitute it.
Atropine recalls
From the FDA Enforcement database. A recall covers specific lots — not the drug as a whole.
How long atropine keeps
The date on a sealed pack is not the only one: some atropine labels start a second clock once the product is opened or mixed, as short as 24 hours.
Does atropine expire? The in-use limits and storage rules from its labelsAtropine and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for atropine: levels in milk, effects in breastfed infants, and the drugs it would consider insteadNo information is available on the use of atropine during breastfeeding. Long-term use of atropine might reduce milk production or milk letdown, but a single systemic or ophthalmic dose is not likely to interfere with breastfeeding. During long-term use, observe for signs of decreased lactation (e.g., infant insatiety, poor weight gain).
National Institute of Child Health and Human Development, record revised November 15, 2024. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about atropine
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 17,827 reports naming atropine, and the FDA flagged 83% 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:
- diarrhoea1,835 reports
- nausea1,408 reports
- fatigue1,150 reports
- vomiting860 reports
- dyspnoea788 reports
- pyrexia747 reports
- headache726 reports
- hypotension724 reports
Read these as a signal, not a rate. A report does not mean atropine 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 August 25, 2026.
Related calculators
Frequently asked questions
What is Atropen?
Each prefilled ATROPEN single-dose autoinjector provides an intramuscular dose of atropine, a cholinergic muscarinic antagonist in a self-contained unit, designed for self- or caregiver-administration. When activated, the ATROPEN 0.25 mg autoinjector delivers 0.21 mg atropine base (equivalent to 0.25 mg atropine sulfate) in 0.3 mL of sterile pyrogen-free solution containing citrate buffer, sodium chloride, and Water for Injection. The pH range is 4.0 to 5.0. When activated, the ATROPEN 0.5 mg autoinjector delivers 0.42 mg atropine base (equivalent to 0.5 mg atropine sulfate), the ATROPEN 1 mg autoinjector delivers 0.84 mg atropine base (equivalent to 1 mg atropine sulfate), and the ATROPEN 2 mg autoinjector delivers 1.67 mg atropine base (equivalent to 2 mg atropine sulfate). Each 0.5 mg, 1 mg, and 2 mg ATROPEN autoinjector delivers atropine in 0.7 mL of sterile pyrogen-free solution containing 12.5 mg glycerin, 2.8 mg phenol, citrate buffer, and Water for Injection. The pH range is 4.0 to 5.0. Atropine occurs as white crystals, usually needle-like, or as a white, crystalline powder.
What kind of drug is atropine?
The FDA classifies atropine as an anticholinergic. Anticholinergic drugs block acetylcholine, the chemical messenger of the body's "rest and digest" nervous system, by occupying its muscarinic receptors. This eases muscle spasms, dries up secretions, relaxes the bladder and airways, and speeds the heart, depending on the tissue. 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 atropine 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 atropine 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 atropine sold under?
We track 3 atropine-containing products in the U.S.: Atropen, Atropine Sulfate and Isopto Atropine. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does atropine come in?
Across the brands we track, atropine is currently marketed as injectable and solution, 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 atropine?
Yes. Our catalog lists 1 generic atropine 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.
Has atropine been recalled?
The FDA's Enforcement database lists 1 recall record whose product description mentions atropine. The most recent: Atropine Sulfate Ophthalmic Solution (Dec 16, 2024). A recall applies to specific lots, not to the drug as a whole — check the record for the affected lot numbers.
Cite this page
- APA
- pharmaranks. (2026, July 24). Atropine: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/atropine
- MLA
- “Atropine: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/atropine.
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 atropine on DailyMed (NIH) ↗.