Atropine (0.01% w/v) is a sterile ophthalmic solution containing the antimuscarinic alkaloid atropine sulfate. In this low concentration, it is primarily used as a mydriatic and cycloplegic agent for diagnostic purposes and for the management of progressive myopia in children. It acts as a non-selective muscarinic acetylcholine receptor antagonist, blocking the action of acetylcholine on the sphincter muscle of the iris and the ciliary muscle, leading to pupil dilation (mydriasis) and paralysis of accommodation (cycloplegia).
Adult: Not typically used for myopia control in adults. For cycloplegic refraction: One drop of higher concentration (0.5% or 1%) instilled 1 hour before procedure. For 0.01% (off-label): Usually one drop in each eye once daily at bedtime.
Note: 1. Wash hands. 2. Tilt head back. 3. Gently pull lower eyelid down to form a pouch. 4. Instill one drop into the conjunctival sac. 5. Close eyes gently and apply pressure to the lacrimal sac (inner corner of eye) for 1-2 minutes to minimize systemic absorption (nasolacrimal occlusion). 6. Do not blink excessively. 7. Wait at least 5-10 minutes before instilling any other eye drops. Avoid contact of dropper tip with eye or any surface to prevent contamination.
Atropine competitively blocks the action of acetylcholine at postganglionic muscarinic receptors in the sphincter pupillae and ciliary muscles of the eye. This blockade inhibits parasympathetic nerve impulses, leading to unopposed sympathetic activity. The result is relaxation of the sphincter pupillae (causing mydriasis) and relaxation of the ciliary muscle (causing cycloplegia or paralysis of accommodation). The exact mechanism for myopia control is not fully elucidated but is thought to involve retinal dopamine release, non-muscarinic receptor pathways, and inhibition of scleral remodeling.
Pregnancy: Category C: Animal reproduction studies have shown an adverse effect on the fetus. There are no adequate and well-controlled studies in humans. Use only if the potential benefit justifies the potential risk to the fetus. Systemic atropine crosses the placenta and may cause fetal tachycardia.
Driving: May cause blurred vision, photophobia, and dizziness. Patients should not drive or operate machinery until vision clears, which can take several days after discontinuation.
| Other anticholinergic drugs (e.g., Ipratropium, Oxybutynin, Tricyclic Antidepressants, Phenothiazines) | Additive systemic anticholinergic side effects (dry mouth, constipation, urinary retention, tachycardia, confusion). | Major |
| Potassium Chloride (wax-matrix formulations) | Increased risk of severe gastrointestinal lesions due to reduced GI motility. | Moderate |
| Cholinergic drugs (e.g., Pilocarpine, Physostigmine, Donepezil) | Atropine antagonizes the effects of these drugs. | Major |
| Digoxin | Increased serum digoxin levels due to reduced GI motility, potentially leading to toxicity. | Moderate |
| Levodopa | Reduced absorption of levodopa from the GI tract. | Moderate |
Same composition (Atropine (0.01% w/v)), different brands: