atropine ophthalmic

Action and Spectrum

Actions and Spectrum 

Action: 

 atropine is an anticholinergic drug that works by blocking the effects of acetylcholine, a neurotransmitter responsible for stimulating the muscles of the eye. By blocking the cholinergic receptors in the eye, atropine causes the pupil to dilate (mydriasis) and prevents the focusing muscle of the eye (ciliary muscle) from contracting (cycloplegia). This results in the temporary loss of near vision and the ability to accommodate or focus on close objects.  

Spectrum:  

atropine ophthalmic is primarily used for diagnostic and therapeutic purposes in ophthalmology. It has a broad spectrum of applications, including: 

Diagnostic purposes: 

Pupil dilation for ophthalmologic examinations and procedures. 

Cycloplegic refraction: By paralyzing the ciliary muscle, drug helps determine the refractive error of the eye, particularly in children who may not cooperate with regular refraction tests. 

Therapeutic purposes: 

Treatment of certain eye conditions: The drug can be used to manage and prevent conditions like uveitis (inflammation of the uvea), iritis (inflammation of the iris), and certain types of keratitis (corneal inflammation). 

Amblyopia (lazy eye) treatment: The drug can be prescribed to blur the vision in the stronger eye temporarily, encouraging the use and development of the weaker eye. 

Drug Interaction

Adverse Reaction

Frequency not defined  

Physostigmine 

Increased intraocular pressure 

Drowsiness 

Dry eyes 

Local irritation 

Vascular congestion 

Blurred vision 

Dermatitis 

Hyperemia 

Edema 

Exudate 

Follicular conjunctivitis 

Hyperreactive response in Down’s syndrome children (atropine) 

Black Box Warning

Black Box Warning:  

None  

Contraindication / Caution

Contraindication/Caution:  

Hypersensitivity: Individuals who have a known hypersensitivity should not use atropine ophthalmic. 

Glaucoma: atropine can increase intraocular pressure, which is harmful to individuals with glaucoma, a condition characterized by increased pressure within the eye. It is contraindicated in narrow-angle glaucoma. 

Adhesions and Synechiae: atropine should not be used in patients with adhesions or synechiae, which are conditions characterized by the attachment of the iris to other structures within the eye. 

Ulcerative Colitis: atropine may worsen symptoms of ulcerative colitis, a chronic inflammatory bowel disease. Therefore, it should be avoided in individuals with this condition. 

Intestinal Obstruction: atropine can inhibit gastrointestinal motility and should be avoided in individuals with intestinal obstruction, as it may exacerbate the condition. 

Prostate Hypertrophy: drug can cause urinary retention and should be used with caution or avoided in individuals with prostate hypertrophy, a condition characterized by an enlarged prostate gland. 

Cardiac Conditions: drug can increase heart rate and may be contraindicated in individuals with certain cardiac conditions such as tachycardia, coronary artery disease, or myocardial infarction. 

Pregnancy / Lactation

Pregnancy warnings:     

Pregnancy category: N/A 

Lactation: Excreted into human milk is unknown 

Pregnancy Categories:         

Category A: Studies that were well-controlled and met expectations revealed no risk to the fetus in either the first or second trimester. 

Category B: There were a lack of studies on pregnant women and no evidence of risk to the fetus in animal experiments.   

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.   

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category

Pharmacology

Pharmacology:  

atropine ophthalmic is a medication that belongs to the class of anticholinergic drugs. It is commonly used in ophthalmology to dilate the pupil (mydriasis) and temporarily paralyze the muscles of the eye (cycloplegia) for various diagnostic and therapeutic purposes.   

Pharmacodynamics:  

The drug acts as a competitive antagonist at muscarinic receptors, specifically the M1, M2, M3, M4, and M5 subtypes. By binding to these receptors, atropine inhibits the binding of acetylcholine (a neurotransmitter) and blocks the subsequent downstream signaling pathways mediated by these receptors. 

Pupil Dilation: One of the prominent effects of atropine ophthalmic is pupillary dilation (mydriasis). The medication blocks the muscarinic receptors present on the pupillary sphincter muscle of the iris, preventing the constriction of the pupil. This dilation allows for improved visualization of the posterior segment of the eye during diagnostic procedures or examinations.   

Pharmacokinetics: 

Absorption 

When applied to the eye, it is absorbed through the conjunctiva (the thin membrane covering the eye) and can enter the systemic circulation. 

Distribution 

The medication is dispersed throughout the body using the circulatory system. It has the ability to pass through the blood-brain barrier and access the central nervous system, which could result in systemic side effects. 

Metabolism 

The  metabolism of drug take place in the liver by enzymes, primarily cytochrome P450 3A4 (CYP3A4). It undergoes hepatic metabolism to form metabolites, including noratropine and tiglyl alcohol, among others. 

Excretion and elimination 

 After metabolism, the metabolites of atropine are excreted primarily in the urine. Small amounts may also be excreted in feces and through the sweat glands. 

Adminstartion

Administration:  

Administer the eye drops: Hold the dropper close to the eye, without touching the eye or any other surface. Squeeze the prescribed number of drops into the lower eyelid pocket. Be careful not to squeeze the dropper too hard to prevent excessive force or discomfort. 

Close your eye: Close your eye gently but do not blink immediately after administering the drops. This allows the medication to distribute evenly over the eye surface. 

Apply gentle pressure: Use a clean tissue or your finger to apply gentle pressure. 

This prevents the medication from draining into the tear ducts and getting absorbed systemically. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: atropine ophthalmic 

Why do we use atropine ophthalmic?  

Pupil dilation: atropine is used to dilate the pupil (mydriasis) during eye examinations. It is often used prior to procedures like retinal examinations or fundus photography. 

Refraction testing: atropine can be used to temporarily paralyze the focusing muscle of the eye (ciliary muscle), allowing for more accurate refraction measurements. This helps determine the appropriate lens prescription for corrective eyewear or contact lenses. 

Treatment of certain eye conditions: atropine ophthalmic drops can be used to treat specific eye conditions, including amblyopia (lazy eye) and strabismus (misalignment of the eyes). By temporarily blurring the vision in the stronger eye, atropine encourages the weaker eye to become more active and strengthen visual acuity. 

Management of uveitis: atropine eye drops can help manage this condition by dilating the pupil and reducing pain caused by light sensitivity. Additionally, atropine helps prevent the formation of adhesions between the iris and the lens, which can lead to complications. 

Treatment of spasm of accommodation: atropine can be used to alleviate spasm of accommodation, a condition characterized by excessive constriction of the pupil and focusing difficulties. By relaxing the ciliary muscle, atropine helps restore normal focusing ability.