Contact Lens Safety from a Pharmacovigilance Perspective

Pharmacovigilance is traditionally associated with monitoring the safety of medicines, vaccines, and biologics. However, patient safety also includes medical devices such as contact lenses, which are used by more than 140 million people worldwide. While they provide effective vision correction, contact lens risks include eye irritation, infections, microbial keratitis, behavioural factors, and inadequate lens care. For pharmacovigilance professionals, these risks highlight the importance of monitoring not only products but also real-world use. Clinical case reports, literature updates, regulatory communications, and contact lens safety news can provide early safety signals that help identify emerging risks before they become widely recognised.

Through continuous monitoring of medical literature, DrugCard helps safety teams detect and assess these signals, supporting proactive risk management and improving patient safety for both medicines and medical devices.

Contact Lens Safety: Why It Matters Beyond Eye Care

Safe contact lens use is about more than preventing everyday eye problems. For pharmacovigilance professionals, it is part of a broader system of patient safety, medical device vigilance, and continuous safety monitoring. Unlike medicines, contact lens complications often result from interactions among the device, user behaviour, hygiene practices, and environmental exposure rather than the device alone.

Monitoring these events helps identify emerging safety concerns, including infections, antimicrobial resistance, product quality issues, and unexpected patterns associated with contact lens use. Evidence comes from multiple sources, including clinical case reports, scientific literature, regulatory updates, and post-market surveillance. Together, these data support earlier detection of potential safety signals and more informed risk assessment.

Viewing contact lens-related safety through this wider pharmacovigilance perspective helps improve both patient outcomes and the safe use of medical devices in routine clinical practice.

Common Contact Lens Risks Pharmacovigilance Teams Should Track

Contact lens-related adverse events rarely have a single cause. In many cases, complications develop through a combination of patient behaviour, device characteristics, environmental exposure, and microbial contamination. Understanding these contributing factors helps pharmacovigilance teams evaluate published case reports, identify emerging safety signals, and distinguish isolated incidents from broader safety trends. For this reason, these safety concerns are commonly assessed from two complementary perspectives: behavioural factors related to lens use and product- or device-related factors that may influence patient safety.

Behavioural Risk Factors

Many contact lens complications are associated with user behaviour rather than product defects. Published case reports frequently describe risks associated with extended wear, sleeping in lenses, poor hand hygiene, water exposure, delayed lens replacement, or improper lens cleaning and storage case cleaning. These factors can increase the likelihood of eye irritation, microbial contamination, and serious infections.

Many complications can be prevented through appropriate lens care. Contact lens wearers should wash their hands before wearing contact lenses or handling lenses, always remove contact lenses before sleep, and avoid exposing them to tap water, swimming pools, or a hot tub. It is also recommended to insert lenses before applying makeup and avoid direct exposure to aerosol products, as these practices may increase the risk of contamination and eye infections.

For pharmacovigilance teams, behavioural information provides important context for assessing whether adverse events result from device performance, patient practices, or a combination of both.

Product-Related and Device-Related Risks

Safety monitoring should also consider risks associated with the contact lens itself or its supporting products. Lens materials, oxygen permeability, care solutions, storage cases, manufacturing quality, and product recalls may all influence patient outcomes. Monitoring reports of contaminated solutions, device defects, or unexpected safety concerns helps identify potential product-related signals before they become widespread. By evaluating behavioural and device-related factors together, pharmacovigilance professionals can better understand emerging safety trends, support evidence-based risk assessments, and contribute to safer use of contact lenses in clinical practice.

Proper maintenance of contact lenses and accessories is equally important. Patients should use fresh contact lens solution, regularly replace the lens case, keep the lens case clean, allow it to air dry, and never reuse or fail to rinse care solutions as directed by the manufacturer or eye care practitioner. For some contact lens wearers, daily disposable lenses may reduce the risk of contamination compared with reusable lenses.

Contact Lens Safety Issues: An Overview

Contact lens-related adverse events range from mild, self-limiting conditions to serious complications that require urgent ophthalmic care. For pharmacovigilance professionals, understanding the spectrum of these events is essential for evaluating clinical case reports, identifying emerging safety signals, and supporting risk assessment. Most complications fall into two broad categories: non-infectious and infectious. Although their underlying causes differ, both can affect treatment adherence, visual outcomes, and long-term ocular health.

Non-Infectious Complications

Non-infectious complications are usually associated with reduced oxygen supply, mechanical irritation, or hypersensitivity reactions rather than infection. They often develop gradually and may be reversible when recognised early and managed appropriately.

Commonly reported conditions include:

• Epithelial oedema and microcysts are often associated with inadequate oxygen permeability.
• Superficial punctate keratitis is linked to instability of the tear film and ocular surface irritation.
• Long-term changes in corneal shape cause corneal warpage during contact lens wear.
• Conjunctival reactions, including giant papillary conjunctivitis and superior limbic keratoconjunctivitis.
• Corneal neovascularisation, where chronic hypoxia stimulates blood vessel growth into normally avascular corneal tissue.

Patients with non-infectious complications may experience redness, discomfort, pain, foreign body sensation, or increased sensitivity, even without evidence of infection. Although these symptoms are usually reversible, persistent eye problems should be evaluated promptly to prevent progression and maintain long-term ocular health.

Although these complications rarely threaten vision immediately, they may reduce contact lens tolerance and increase the risk of further ocular problems if left unrecognised.

Infectious Complications

Infectious complications remain the greatest safety concern because they can progress rapidly and lead to permanent vision impairment. Among these, microbial keratitis (MK) is the most clinically significant condition and requires prompt diagnosis and treatment.

The most frequently reported pathogens include:

• Pseudomonas aeruginosa is the leading cause of contact lens-associated bacterial keratitis.
• Acanthamoeba spp. causes severe, often difficult-to-treat keratitis, particularly after water exposure.
• Fusarium spp. are fungal pathogens associated with contaminated contact lens care solutions.
• Serratia marcescens, an emerging cause of aggressive bacterial keratitis, has been described in several published case reports.

Typical warning signs include redness, severe pain, blurred vision, excessive tearing, and sensitivity to light. If these symptoms develop, patients should seek immediate evaluation by an eye doctor or optometrist, as a corneal infection may progress to corneal ulcers, requiring intensive treatment with antimicrobial eye drops. Delayed diagnosis can lead to vision loss, permanent visual impairment, or, in rare cases, blindness.

Epidemiological studies show that overnight contact lens wear increases the risk of microbial keratitis by approximately five- to seven-fold, while poor hygiene and inappropriate lens care further increase the likelihood of infection. These findings reinforce the importance of continuous monitoring of published evidence to identify changing pathogen patterns and emerging ocular safety concerns.

Contact Lens Safety News as a Source of Emerging Signals

Scientific publications remain a cornerstone of pharmacovigilance, but they are only part of the safety landscape. Early signals may also emerge from regulatory alerts, product recalls, public health updates, and professional society communications. Monitoring this broader information ecosystem helps identify emerging pathogens, changes in antimicrobial resistance, device quality concerns, and new risk factors before they are widely reflected in the scientific literature. By combining these sources with continuous literature monitoring, DrugCard helps pharmacovigilance teams detect and evaluate potential safety signals more effectively.

Case Report Spotlight: Serratia marcescens keratitis

Thanks to DrugCard’s monitoring of the literature, a noteworthy case was identified. This case provides invaluable insights into both clinical management and risk prevention.

A 22-year-old medical student developed sudden Serratia marcescens keratitis after using soft contact lenses. She admitted to occasionally showering while wearing lenses and had exceeded the recommended 4-week replacement schedule by wearing monthly disposables for 5 weeks. 

Clinical findings included conjunctival injection, anterior chamber inflammation, and a corneal abscess with epithelial defect. Initial treatment with moxifloxacin failed. The regimen was escalated to fortified vancomycin, ceftriaxone, and voriconazole. Once cultures confirmed S. marcescens, therapy was streamlined to fortified ceftriaxone, with full recovery and minimal scarring at one month; visual acuity returned to 20/20.

Lessons for Pharmacovigilance and Ocular Safety Monitoring

This case illustrates how individual clinical reports can provide valuable insights for pharmacovigilance and ocular safety monitoring. Beyond documenting a rare infection, it highlights behavioural, microbiological, and clinical factors that may contribute to earlier detection of safety signals and more effective risk management.

Behaviour Matters in Device Safety

Unlike adverse drug reactions, which are often driven by pharmacological mechanisms, many contact lens-related complications result from how the device is used. Extended wear, poor hygiene, delayed lens replacement, and water exposure remain well-recognised risk factors for microbial keratitis. Capturing these behavioural details in case reports and safety assessments helps pharmacovigilance teams distinguish product-related concerns from preventable patterns of device use and supports more targeted risk minimisation measures.

Antimicrobial Resistance in Ocular Pathogens

The initial lack of response to moxifloxacin also highlights the growing challenge of antimicrobial resistance in ocular infections. Culture-guided treatment enabled targeted therapy after Serratia marcescens was identified, demonstrating the importance of microbiological confirmation whenever clinically appropriate. Monitoring trends in resistance reported in the medical literature can help safety professionals recognise changing susceptibility patterns and support evidence-based treatment recommendations.

Interdisciplinary Safety Monitoring

This case sits at the intersection of ophthalmology, microbiology, infectious diseases, and pharmacovigilance. It demonstrates that effective medical device vigilance requires collaboration across disciplines and the integration of diverse evidence sources. By combining clinical case reports, literature monitoring, and microbiological data, pharmacovigilance teams can identify emerging safety signals earlier and help ensure the safer use of contact lenses in routine clinical practice.

How Literature Monitoring Supports Contact Lens Safety

The identification of this rare case underscores the importance of continuous monitoring of the medical literature in pharmacovigilance. While spontaneous reporting systems remain essential, they may not capture every device-related complication or emerging infectious threat. Published case reports, observational studies, regulatory communications, and safety alerts can all provide valuable early safety signals.

Effective monitoring should include not only scientific publications but also reports describing unusual pathogens, antimicrobial resistance, product quality issues, and emerging trends associated with contact lens use. Together, these sources provide a more comprehensive understanding of the evolving safety profile of contact lenses.

Because relevant evidence is dispersed across numerous journals and information sources, manual literature monitoring may overlook clinically important publications. Platforms such as DrugCard help pharmacovigilance teams continuously identify and assess relevant literature, enabling earlier detection of emerging drug- and device-related risks and supporting more informed safety assessments.

Contact Lens Safety Tips vs Pharmacovigilance Insights

For contact lens users, safety starts with good hygiene, following replacement schedules, avoiding water exposure, and seeking prompt medical attention if symptoms develop. These measures help reduce the risk of preventable eye complications.

From a pharmacovigilance perspective, the focus is broader. Safety professionals monitor clinical case reports, emerging pathogens, antimicrobial resistance, behavioural risk factors, and device-related issues to identify trends that may affect larger patient populations. Together, patient education and continuous safety monitoring contribute to safer contact lens use and support evidence-based risk management.

Conclusion

The safe use of contact lenses extends far beyond ophthalmology – it is a vital pharmacovigilance concern. The case of Serratia marcescens keratitis demonstrates how everyday user behaviours, the growing challenge of antimicrobial resistance, and timely clinical decision-making intersect to shape patient safety outcomes. While many complications can be prevented through appropriate use and hygiene, continuous monitoring remains essential for identifying emerging risks that may not be apparent in routine clinical practice. Platforms like DrugCard, which can detect rare but clinically significant cases in the medical literature, provide an additional layer of vigilance. These insights help pharmacovigilance professionals identify early signals that might otherwise be overlooked.

Ultimately, integrating these lessons into routine practice strengthens our ability to ensure that contact lenses remain a tool for better vision and a safe and reliable option for millions of users worldwide.

FAQ on Contact Lens Safety

What are the most important contact lens risks to monitor?

Key risks include eye irritation, microbial keratitis, other infections, antimicrobial resistance, poor hygiene, extended wear, water exposure, and product-related issues that may contribute to adverse events and patient harm.

How does ocular safety monitoring support patient safety?

Continuous surveillance of eye-related safety events helps identify emerging risks, detect safety signals, monitor infection trends, and support evidence-based risk assessment, enabling earlier interventions and improved patient safety outcomes.

Why is contact lens safety news useful for safety teams?

Regulatory updates, product recalls, public health alerts, and other safety-related developments complement scientific literature by highlighting emerging issues that may indicate new or evolving safety concerns.

How can DrugCard support contact lens safety monitoring?

DrugCard continuously monitors medical literature and other relevant sources, helping pharmacovigilance teams identify case reports, emerging safety signals, and evidence to support timely safety assessments and risk management.