Monoprost

Latanoprost

Method of action: Antiglaucomatous, Intraocular Pressure Lowering, Ophthalmologicals

Treatment option: Hypertension, Glaucoma

Medically reviewed

Marina Burgos

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Monoprost

Property	Description
Active Ingredient	Latanoprost
Form	Ophthalmic solution (Eye drops)
Pharmacological Class	Ocular Hypotensive Agent
General Purpose	Reduction of intraocular pressure
Key Feature	Preservative-free formulation

Monoprost is an ophthalmic preparation containing the active ingredient Latanoprost, classified as a prescription-only medicine designed for the management of pressure inside the eye. Its primary pharmacological function is as an Antiglaucoma preparation, operating specifically as an Ocular Hypotensive Agent. This medication belongs to the class of Prostaglandin F2α analogues, which are synthetic derivatives widely clinically recognized for their role in managing ocular hypertension.

What Type of Medicine is Monoprost (Latanoprost)?

Monoprost is an Ocular Hypotensive Agent designed to safely and effectively reduce elevated pressure within the eye. The active substance, Latanoprost, achieves this by acting as a prostanoid receptor agonist, which means it stimulates specialized receptors in the eye's tissues. This selective action is understood to increase uveoscleral outflow. This means the medication fundamentally works by making the eye's natural drainage pathways more efficient. The general purpose of this targeted, synthetic mechanism is to provide a consistent, non-invasive method for pressure management, maintaining pressure reduction for at least 24 hours.

Composition, Form, and General Purpose

Monoprost is formulated as a sterile ophthalmic solution delivered as eye drops via the ocular route in a single-dose unit container. This preparation contains the single active ingredient, Latanoprost, dissolved in an aqueous solution base. A defining characteristic of Monoprost, which differentiates it from several traditional brands, is its designation as a preservative-free formulation. This formulation avoids the use of common preservatives, such as benzalkonium chloride, which can sometimes cause irritation with long-term use. The fundamental general purpose of the medication is to lower elevated intraocular pressure, serving as a critical tool for sustained pressure management.

What side effects are possible with Monoprost?

Possible Side Effects and Safety Information

The safety profile of Monoprost (Latanoprost) is formally classified based on frequency and affected physiological systems, as documented by official regulatory authorities.

Frequency-Classified Adverse Reactions

The most commonly documented adverse reactions primarily affect the eye, though systemic effects are also listed. Frequencies are based on regulatory standards:

Very Common (affecting more than 1 in 10 patients): These include increased pigmentation of the iris (a gradual and potentially permanent color change), conjunctival hyperaemia (eye redness), and localized ocular irritation (such as burning or foreign body sensation). Changes to the eyelashes and vellus hair (increased length, thickness, or number) are also classified as Very Common.
Common (affecting 1 to 10 in 100 patients): Ocular pain, blepharitis (eyelid inflammation), dry eye, and punctate keratitis (superficial corneal inflammation) are documented at this frequency.

Less common reactions (Uncommon and Rare) involve other systems, including headache, dizziness, skin rash, and serious events like asthma exacerbation or new onset.

Safety Considerations and Restrictions

Official labeling addresses specific constraints and potential serious reactions:

Serious Adverse Reactions: The medication carries a documented risk of Macular Oedema, particularly in patients who are aphakic or pseudophakic (lacking or having an implanted lens) or those with other risk factors for cystoid macular oedema. Rare but severe reactions include Toxic Epidermal Necrolysis.
Duration-Related Patterns: While iris pigmentation is a permanent change that develops gradually, changes to eyelashes are generally considered reversible upon permanent discontinuation.
Safety Restrictions: Regulatory guidance advises against the simultaneous use of Monoprost with other similar prostaglandin analogues due to the documented potential for a paradoxical increase in intraocular pressure.

These official safety classifications structure the understanding of Monoprost's risk profile, detailing potential reactions by likelihood, affected body system, and specific limitations on use.

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory guidance for Monoprost (Latanoprost) overdose addresses two primary exposure scenarios: excessive topical application and accidental oral ingestion.

Documented Manifestations

In cases of topical over-application, the overdose profile is associated with minor, localized ocular effects. These include ocular irritation, conjunctival hyperaemia (eye redness), and increased eye watering. Regulatory documents state that no other systemic adverse reactions are known to result from ophthalmic overdose alone.

Following accidental oral ingestion, the risk shifts to potential systemic exposure. High systemic doses have been associated with symptoms such as nausea, abdominal pain, dizziness, and fatigue.

Emergency Action Required

Urgent medical attention is necessary if the eye drops are swallowed accidentally by an adult or a child. In this instance, a healthcare professional must be contacted as soon as possible. Treatment for overdose is symptomatic and supportive, and official prescribing information confirms that no specific antidote is known. Depending on the severity of oral ingestion, procedures such as gastric lavage may be considered by medical personnel. For persistent symptoms following only topical over-use, advice should be sought from a doctor.

Therapeutic Uses of Monoprost

What Monoprost Treats: Main Uses and Benefits

Monoprost is commonly used across conditions presenting with acute episodes and is applied in addressing symptoms linked to organ-specific functional stress. Its primary therapeutic domain is focused on providing supportive symptomatic relief for elevated pressure within the eye. Specifically, the medicine is commonly used to help manage conditions characterized by periods of heightened symptoms, such as open-angle glaucoma and ocular hypertension (OHT).

This medicine is considered relevant when supportive symptom management is appropriate. The medicine is applied in clinical settings that involve acute or unstable symptom patterns, which may include symptoms related to systemic imbalance. The management of these conditions is relevant when supportive symptom management is appropriate, particularly in conditions where symptoms may intensify temporarily and affect functional stability.

In scenarios where additional management of discomfort is required, the medicine provides support that helps ease the overall symptom burden and assists with maintaining functional stability. In these contexts, Monoprost is considered relevant for managing the conditions.

“This medicine is commonly used when short-term symptomatic assistance is needed to address symptoms related to heightened physiological activity.”

Quick Fact: Relief for Symptoms related to physical discomfort

Regulatory References

Health Canada Product Monograph

Eligibility and Restrictions for Use

Who Can and Cannot Use Monoprost?

This section outlines the official population eligibility and non-eligibility rules for Monoprost (Latanoprost), based strictly on government regulatory documents.

Monoprost is contraindicated for any patient with a known hypersensitivity (allergy) to the active ingredient Latanoprost or any of the excipients in the ophthalmic solution.

Age and Physiological Restrictions

Population Group	Eligibility Status (Regulatory Wording)
Adults (18+ years)	Eligible for standard use.
Pediatric Patients	Not recommended (Safety and effectiveness not established).
Pregnant Women	Should not be used (Safety not established).
Breastfeeding Women	Should not be used (May pass into breast milk).

Conditional Use and Avoidance

Use of Monoprost should be avoided in cases of active Herpes Simplex Keratitis or active intraocular inflammation, such as iritis or uveitis.

Special caution is required for certain populations, including aphakic patients, pseudophakic patients with a torn lens capsule, or those with a history of intraocular inflammation. Caution is also advised for patients with severe asthma or uncontrolled asthma, and for those with hepatic or renal impairment, due to limited clinical experience in these groups.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Official regulatory documents define the interaction profile of Monoprost (Latanoprost) based predominantly on its local ophthalmic application and constraints on co-administering topical agents.

Pharmacodynamic and Physicochemical Restrictions

Substance Category	Documented Interaction Outcome	Regulatory Requirement
Other Prostaglandin Analogues (Topical Ophthalmic)	Paradoxical elevation in intraocular pressure (IOP) or decreased efficacy.	Co-administration is formally not recommended.
Other Topical Ophthalmic Products (All types)	Potential for reduced absorption or local washout effect.	Must be administered at least five (5) minutes apart.
Thimerosal-Containing Eye Drops	In vitro precipitation of the active substance.	Must be administered at least five (5) minutes apart.
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)	Conflicting reports of either an increase or a decrease in IOP effect.	Use with caution, as officially documented.

Systemic and Non-Medicinal Substance Interactions

Due to the rapid local metabolism and low systemic exposure of latanoprost, no clinically relevant systemic pharmacokinetic interactions involving Cytochrome P450 enzymes are formally documented in official regulatory labeling. Furthermore, the official prescribing information does not document any specific interactions with food, alcohol, herbal products, or dietary supplements.

Mechanism of Action

The mechanism of Monoprost begins with the inactive latanoprost molecule undergoing hydrolysis by esterases in the cornea, forming the biologically active metabolite, latanoprost acid. This metabolite functions as a selective agonist of the Prostanoid FP Receptor , primarily located on ciliary muscle cells.

Activation of this receptor initiates a molecular cascade that includes the upregulation of Matrix Metalloproteinases (MMPs). These enzymes facilitate the degradation and reorganization of the extracellular matrix (ECM) structure surrounding the ciliary muscle fibers. This tissue remodeling causes the muscle to relax and spaces between the fibers to widen, which increases the porousness of the eye's tissues.

This structural change increases the permeability and capacity of the uveoscleral outflow pathway, leading to a greater sustained exit flow of aqueous humor from the anterior chamber. This increase in the eye's drainage capacity is the core physiological effect, resulting in a reduction of intraocular pressure (IOP). The time required for this tissue-level modification results in a maximum effect observed 8 to 12 hours after administration.

Dosage and Administration Information

Administration Procedure

Monoprost is an ophthalmic solution provided in single-dose containers. Proper administration is necessary to ensure the solution is delivered effectively to the eye surface.

Preparation

Before using the eye drops, hands should be washed thoroughly. The single-dose container should be removed from the strip, and the remaining containers should be placed back into the foil sachet. The tip of the container should not come into contact with the eye, eyelids, or any other surfaces to maintain the sterility of the solution.

Application Steps

Positioning: Tilt the head back or lie down.
Creating a Pocket: Use one finger to gently pull down the lower eyelid of the affected eye to create a small pocket.
Instillation: Hold the open single-dose container upside down above the eye. Squeeze the container gently to allow one drop into the pocket formed by the lower eyelid.
Closing the Eye: Close the eye gently. Do not blink or rub the eye immediately after application.
Lacrimal Occlusion: Apply gentle pressure to the inner corner of the eye (near the nose) for approximately one to two minutes. This helps to keep the drop on the surface of the eye and reduces the amount of medication that may enter the bloodstream.

Use with Other Eye Medications

If more than one type of topical ophthalmic medication is being used, the different medications should be administered at least five minutes apart. This prevents the first drop from being washed out by the second.

Contact Lens Wearers

Contact lenses should be removed prior to the instillation of the drops. After application, a period of at least 15 minutes should pass before reinserting the contact lenses.

Disposal

Each single-dose container is intended for a single application only. Any remaining solution should be discarded immediately after use and should not be saved for future doses.

Recent Clinical Evidence

Research evidence / Overview of Studies for Monoprost

This section provides an overview of the official research studies conducted on the active ingredient in Monoprost, latanoprost, detailing the types of evidence available and what the studies explored. It is designed to be a non-advisory summary of the scientific literature.

Evidence for Use in Primary Open-Angle Glaucoma and Ocular Hypertension

The research base for latanoprost includes numerous large-scale Randomized Controlled Trials (RCTs) and systematic reviews, which provide extensive evidence for the study of outcomes. These trials primarily examined the medication in adults with Primary Open-Angle Glaucoma (POAG) and Ocular Hypertension (OHT), conditions related to pressure within the eye. Researchers monitored the main outcome of Intraocular Pressure (IOP), tracking the mean pressure change from the start of the study.

Comparative research was studied for how latanoprost was studied in comparison to other treatments. The findings describe patterns observed in the studies where IOP measurements showed changes over the study period. Comparative trials exploring the preservative-free formulation (Monoprost) against the standard preserved latanoprost reported how symptoms evolved in the observed populations, with some data indicating patterns related to perceived discomfort being reported with differing frequency when using the preservative-free option.

Research on the Preservative-Free Formulation

The preservative-free formulation of Monoprost was studied for its potential role in patients sensitive to common preservatives, such as benzalkonium chloride. These studies were applied in studies examining patient-reported experiences and outcomes linked to inflammatory or irritative states on the ocular surface. Research explored whether removing the preservative was studied alongside similar measurements of IOP. While the short-term findings regarding outcomes related to physical discomfort were observed in some studies, the follow-up durations were limited in many of these pivotal comparison trials.

Research in Normal-Tension Glaucoma and Specific Populations

Research was studied for latanoprost in patient groups including those with Normal-Tension Glaucoma (NTG). For NTG, the studies focused on outcomes reflecting daily functioning, such as the long-term preservation of the visual field. The studies observed how symptoms and disease progression were monitored over extended periods. This evidence contributes to the broader evidence landscape, as the research describes patterns where IOP measurements were evaluated alongside disease progression markers in this specific patient group.

Key Studies & References

Frequently Asked Questions (FAQ)

Common questions about Monoprost (FAQ)

Q: How soon after starting Monoprost will I notice a drop in my eye pressure?

Official product information indicates that the reduction in elevated eye pressure, known as intraocular pressure (IOP), is reported to begin approximately three to four hours after the eye drops are administered. The medication is reported to achieve its maximum pressure-lowering effect between eight and twelve hours following application.

Q: Is Monoprost effective for the long-term management of glaucoma?

Regulatory documents state that Monoprost (latanoprost) is specifically indicated for the sustained reduction of elevated intraocular pressure in patients diagnosed with conditions such as open-angle glaucoma or ocular hypertension. Safety data from some clinical studies involving latanoprost are available for periods of up to five years, and the medication is intended for sustained pressure management.

Q: What are the differences between Monoprost (preservative-free) and the standard preserved latanoprost?

Monoprost is a preservative-free formulation of latanoprost. Studies have indicated that the preservative-free formulation is equally effective at reducing eye pressure as the preserved formulation. Comparative data has indicated patterns related to perceived discomfort being reported with differing frequency when using the preservative-free option.

Q: Can I wear my contact lenses when using Monoprost?

Regulatory documents state that contact lenses must be removed before the eye drops are applied. This is a standard precautionary measure. Lenses may be reinserted 15 minutes after the administration of Monoprost.

Q: Can I drink alcohol while I am using Monoprost?

According to the official regulatory prescribing information for Monoprost, there are no specific interactions documented with alcohol. Patients with questions about use should refer to the official labeling.

Q: How do I know if the eye drops are still good after opening the foil sachet?

Monoprost comes in single-dose containers sealed within a foil sachet. After the sachet is opened, the single-dose containers are stated to be used within 7 to 10 days, depending on the specific packaging instructions. The individual unit dose container is stated to be used immediately after opening and discarded after use.

Q: What are the signs of a serious allergic reaction to Monoprost?

The official product information states that the medicine is contraindicated (should not be used) if a patient has a known hypersensitivity or allergy to latanoprost or any of its ingredients. Reported adverse reactions include rash. The serious skin condition toxic epidermal necrolysis has also been reported in post-marketing experience.

Q: Is there any food or drink I need to avoid while using Monoprost?

Official prescribing information does not document any specific interactions with food, dietary supplements, or herbal products.

How should Monoprost be stored and disposed of?

The storage and disposal of Monoprost (latanoprost) must follow specific rules to maintain its integrity, particularly due to its preservative-free, single-dose formulation.

Storage Conditions and Stability

Scope Element	Official Regulatory Requirement
Storage Temperature	Store below 25 C.
Light Protection	Must be protected from light and stored in the original outer carton.
After Sachet Opening	Use the single-dose containers within 7 to 10 days (varies by pack size).
After Container Opening	The solution must be used immediately and the container discarded after use.

Disposal and Child Safety

Monoprost must be kept out of the sight and reach of children.

Unused or expired medicine must be disposed of according to local requirements; it must not be thrown away via wastewater or household waste. Consult a pharmacist for proper disposal instructions.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.