atropine sulfate at a glance
Medicine class
Antimuscarinic, also called an anticholinergic.
Licensed roles
Progressing childhood myopia, clinically important slow heart rate, selected poisonings and perioperative care.
Routes
Eye drops or injection, depending on the indication and product.
What is atropine sulfate used for?
Products are licensed for different clinical settings.
Slowing progressing myopia in eligible children under specialist eye care.
Treating clinically important slow heart rate.
Reducing salivary and bronchial secretions and preventing vagal reactions around anaesthesia or surgery.
Counteracting muscarinic effects when neostigmine reverses non-depolarising muscle relaxation.
Treating poisoning caused by cholinesterase inhibitors, organophosphate pesticides and certain muscarinic mushrooms.
How does atropine sulfate work?
Atropine reversibly blocks muscarinic acetylcholine receptors. This reduces secretions, relaxes some smooth muscle and removes vagal slowing of the heart. In the eye it enlarges the pupil and reduces focusing ability. How it slows myopia is not fully established.
atropine sulfate preparations and strengths
Eye drops
Route: Ophthalmic
Strengths: 0.1 mg/mL, 1.0% w/v, 1%, 1% w/v
Injection
Route: Parenteral
Strengths: 600 micrograms/1 mL, 600 micrograms/mL, 1 mg/1 mL
How to take atropine sulfate
Injections are administered by trained healthcare professionals. For eye drops, wash your hands, avoid touching the bottle tip to the eye or eyelids, and gently press the inner corner of the closed eye after application.
Remove contact lenses before using the selected myopia eye drops.
Apply eye ointments after other eye medicines.
Keep eye drops out of children’s reach because swallowing them can cause poisoning.
atropine sulfate side effects
Common or expected effects
- Sensitivity to bright light, blurred vision and enlarged pupils with eye drops.
- Eye irritation, discomfort, pain or a foreign-body sensation.
- Headache.
- Systemic effects can include dry mouth, flushing, constipation, difficulty passing urine, dizziness and heart-rate changes.
Get urgent medical advice
- Severe allergic reaction with swelling, breathing difficulty or collapse.
- Painful red eye, sudden blurred vision, haloes, headache, nausea or vomiting.
- Marked confusion, hallucinations, delirium, seizures or profound drowsiness.
- Severe overheating, very fast or irregular heartbeat, breathing difficulty or inability to pass urine.
atropine sulfate in pregnancy
Atropine crosses the placenta, and evidence in pregnancy is limited. The selected eye drops should be used only when considered absolutely necessary, particularly during the final three months; injections should be used only when considered essential. Discuss treatment with the relevant specialist or prescriber, recognising that urgent treatment may still be necessary.
atropine sulfate while breastfeeding
Atropine passes into breast milk, and infants may be particularly sensitive to antimuscarinic effects. For ongoing eye-drop treatment, the prescriber should weigh breastfeeding benefits against treatment benefits. Limited infant exposure is expected after isolated perioperative injection use; prolonged exposure might reduce milk production or let-down.
atropine sulfate interactions
Tell the prescriber about prescription, non-prescription and eye medicines. Important examples include:
Other antimuscarinic medicines
Antihistamines, some antidepressants, phenothiazines, clozapine, amantadine and disopyramide may increase dry mouth, constipation, urinary retention, blurred vision or confusion.
Pilocarpine, carbachol or physostigmine eye preparations
Atropine may oppose their pupil or glaucoma-related effects.
Metoclopramide or domperidone
Atropine may oppose their effects on gastrointestinal movement.
Common questions about atropine sulfate
Answers are fully visible for fast scanning and source review.
Can atropine sulfate eye drops slow childhood myopia?
Yes. The selected eye-drop product is licensed to slow progressing myopia in eligible children and requires specialist initiation and follow-up.
Does atropine sulfate correct existing short-sightedness?
No. It is intended to slow further progression; glasses or contact lenses may still be needed to correct vision.
Why does atropine sulfate make light seem brighter?
It enlarges the pupil and temporarily reduces the eye’s focusing response, allowing more light to enter.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.