A Comprehensive Review of Oral Dissolving Strips and its Use in Supplements

Introduction

Oral dissolving strips, sometimes called oral thin films or mouth dissolving films, are an advanced type of solid product designed to break down quickly when they touch saliva inside your mouth. These products are usually thin and flexible. They offer a significant alternative to common forms like tablets and capsules, especially for people who have trouble swallowing.

The importance of these strips lies in their ability to help the body absorb active ingredients faster. For certain compounds, they can increase bioavailability meaning more of the substance enters the bloodstream because they avoid being processed by the liver immediately after absorption (a process called first-pass metabolism). They also improve user compliance because they are easy to take without water. This makes them a convenient option for many people. This report will look closely at how these strips developed, their benefits, drawbacks, and how they are used, focusing particularly on the supplements industry.

Interestingly, the development of this technology wasn't initially for medicine. It started with the desire for easy-to-use breath-freshening products. This suggests the technology was first aimed at consumers, and its potential for delivering medications or supplements was explored later. The various names used for these strips show it's a developing field still settling on standard terms. The ability to bypass liver metabolism suggests that lower doses might be effective for some supplements, potentially reducing side effects.

Historical Overview and Evolution

Early Origins Breath Fresheners

The first types of quick-dissolving films people encountered weren't medicines. They were consumer items for breath freshening or personal care, like dental strips or even soap strips. Listerine PocketPaks, developed by the pharmaceutical company Pfizer, were among the first widely known oral strips. They were marketed simply to freshen breath and introduced a new format for oral care.

This early focus on convenience helped people get used to the idea of oral strips before their use for delivering active ingredients was fully realized. The successful transition from breath fresheners to carriers for medicines and supplements shows a smart reuse of technology based on its ease of use and quick dissolving nature. Consumer acceptance of these non-medical strips likely helped smooth the path for their use in health products.

Emergence as a Drug Delivery System

The idea of fast-dissolving systems specifically for delivering medicine came about in the late 1970s. This was driven by the difficulty of giving traditional pills and capsules to certain groups, mainly children and older adults. These individuals often struggle with swallowing, leading to them not taking their medication correctly and creating choking risks. Oral dissolving strips were developed as a safer, more convenient option. A key part of their development involved using ingredients called super disintegrants and hydrophilic (water-loving) components. These materials ensure the strip dissolves rapidly in saliva, allowing the active ingredient to be absorbed quickly and making it easier for patients to stick to their medication schedule. The initial focus on children and the elderly highlights the need for user-friendly delivery methods. Even fast-dissolving tablets carried some choking risk, which underlined the need for forms like strips that dissolve completely without swallowing a solid piece.

Key Milestones in Pharmaceutical Use

Moving oral dissolving strips from breath fresheners to medical treatments was a major step. Chloraseptic relief strips were an early therapeutic example. These contained benzocaine to treat sore throats, showing the technology could deliver medication locally within the mouth. However, the real proof of concept for delivering drugs systemically throughout the body came with FDA approvals. In 2010, Zuplenz (containing Ondansetron HCl for nausea and vomiting related to chemo/radiotherapy) became the first FDA-approved prescription dissolving film. Suboxone (for opioid dependence) followed soon after. These approvals showed regulatory confidence in the safety and effectiveness of oral dissolving strips for delivering important medications. The early sore throat application likely served as a trial run before the technology was validated for wider systemic drug delivery by regulators like the FDA.

Timeline of Development

The path of oral films has seen steady progress:

• 1960s The concept appeared in scientific literature. Early work explored films for treating plants, leading to paper films with drug solutions patented in 1962. Dr. L. Leslie in the UK is credited with practical development for medicinal use in 1964.

• Late 1970s Fast-dissolving systems were formally invented to address swallowing issues.

• 1977 Schering Aktiengesellschaft (now Bayer) developed films for drug delivery through mouth, vaginal, and nasal routes.

• 1980s Richard and Joseph Fuisz, Garry Myers, and Robert Yang patented key oral film technology. Richard Fuisz became a leader in the field through Fuisz Technologies.

• 1996 A related technology, the first orally disintegrating tablet (ODT) Claritin, received FDA approval.

• Early 2000s Listerine Pocket Strips popularized the format for consumers as breath fresheners.

• 2003 Chloraseptic Relief Strips, the first thin-film product with a drug (benzocaine), were introduced in the US.

• 2010 Zuplenz became the first FDA-approved prescription dissolving film.

• 2017 The global market for oral thin films reached about US$ 2.1 billion, with strong growth projected.

• 2020 Vitamins made up a large portion (32%) of available oral strips, indicating growth in the supplement sector.

• 2021 Market diversity increased with 43 distinct product groups released.

• 2023 The global oral dissolving film market hit USD 0.39 billion, forecasted to grow significantly.

• 2024 Sublingual films (dissolving under the tongue) became dominant (over 70% market share). In the nutraceutical world, dissolving strips accounted for over 30% of new functional supplement launches, featuring brands like Wellbeing Nutrition, DISO, Setu, NuStrips, and others.

This timeline shows oral strip technology moving from consumer goods to accepted pharmaceutical and supplement delivery systems. Recent market growth, especially for supplements, reflects increasing consumer demand for this convenient format. The rise of sublingual films points towards a preference for quick absorption methods.

Advantages of Oral Dissolving Strips

Comparison with Traditional Forms

Oral dissolving strips offer clear benefits over traditional tablets and capsules. Their ease of swallowing is a major plus for people with dysphagia or pill aversion. Unlike pills needing water, strips dissolve quickly in the mouth, making them highly convenient when water isn't available or practical. Strips are also typically more flexible and less likely to break than orally disintegrating tablets (ODTs), which can be fragile. Regarding dose accuracy, strips can be more precise than liquid syrups where measurement mistakes can happen. This ensures consistent intake, which is important for supplements.

Faster Absorption and Bioavailability

A significant advantage is the potential for faster absorption. When a strip dissolves in the mouth, the active ingredient can enter the bloodstream directly through the mouth's lining (oral mucosa). This route avoids the stomach and initial breakdown by the liver (first-pass metabolism), which can inactivate some compounds. Although the mouth lining isn't as permeable as the intestine, it's much more permeable than skin, allowing effective absorption for suitable molecules. Studies show strips release active ingredients quickly, sometimes resulting in higher relative bioavailability compared to standard products.

Ease of Administration

Strips make administration much easier, especially for those with swallowing difficulties like people with dysphagia, children, and older adults. The fear of choking associated with pills is eliminated because the strip dissolves without needing to be swallowed whole. They allow for self-administration easily, even without water. This user-friendliness greatly improves patient compliance, making people more likely to stick to their supplement routines.

Dose Accuracy

Oral dissolving strips provide highly accurate dosing. Unlike liquids, each strip is made to contain a precise amount of the active ingredient. Manufacturing processes focus on evenly distributing the ingredient throughout the film. Some strips even have perforations allowing users to easily divide them for flexible dosing. This accuracy gives consumers confidence in managing their supplement intake safely and effectively.

Disadvantages and Limitations

Limited Loading Capacity

A major limitation is the amount of active ingredient a strip can hold. Generally, strips can feasibly contain between 1 and 30 mg, with a practical maximum around 40 mg for a typical size strip. This means they aren't suitable for supplements requiring large doses. High-dose vitamins or minerals might not be deliverable in this format. Research is exploring ways to increase this capacity, such as using porous film structures or specific chemical techniques.

Taste Masking Challenges

Since the strip dissolves in the mouth, its taste is very important. Many active ingredients, including vitamins and herbal extracts, can be bitter or unpleasant. Effectively masking these tastes is essential for consumer acceptance. Techniques include using sweeteners, flavors, or encapsulating the ingredient. The success of a supplement strip often hinges on achieving a pleasant taste, though this adds complexity to development and manufacturing. 

Brands like STIM Energy Strips use liposomal encapsulated caffeine, which masks the bitterness encountered in other energy strips which use raw caffeine.

Sensitivity to Environment

Oral strips can be sensitive to moisture and temperature. Their thin, water-loving nature means they can absorb moisture, potentially degrading the active ingredient or compromising the strip's structure. They usually need storage in cool, dry places. Special moisture-barrier packaging is often required to maintain stability and safety throughout the product's shelf life. Moisture absorption is a key quality check during manufacturing.

Potential Dose Uniformity Issues

Ensuring every part of the film has the same amount of active ingredient can be challenging, especially if the ingredient doesn't dissolve well in the film-forming solution. Consistent dosing across all strips in a batch is critical for quality control. Special monitoring techniques might be needed during manufacturing, particularly for ingredients that don't dissolve easily in water, to prevent particles from settling unevenly.

Suitability for Specific Ingredients

Not all supplements are suitable for strip delivery. Ingredients that are unstable at mouth pH levels or that could irritate the mouth lining are poor candidates. Ideally, the active ingredient should dissolve well in water and saliva. It should also be partially in a form that can easily pass through the mouth lining at typical mouth pH.

Manufacturing Challenges and Costs

Making oral dissolving strips can be more complex and potentially costlier than making traditional tablets. Scaling up production from lab research to commercial levels presents challenges, like optimizing coating and drying speeds. Maintaining uniform film thickness is also critical. Drying times can be long, especially for heat-sensitive ingredients needing low temperatures, which affects overall efficiency.

Applications in the Supplements Industry

Current Market Landscape

The supplement industry is increasingly using oral dissolving strips, driven by consumer demand for convenient and pleasant ways to take supplements. There's a strong interest in strips that are sugar-free, non-GMO, and vegan-friendly, leading to many herbal and vitamin strips meeting these criteria. The overall market for supplement strips is growing quickly, showing positive reception by both consumers and manufacturers.

Common Types of Supplements Available

A wide variety of supplements now come in strip form. Vitamins like B12, C, D3, K2, and multivitamins are common. Minerals like iron are also available. Herbal extracts such as Ashwagandha, Ginseng, and Curcumin are popular choices. Other specialized supplements delivered via strips include melatonin for sleep, probiotics for gut health, electrolytes for hydration, and even beauty supplements with collagen or hyaluronic acid. This diversity shows the technology's versatility.

Examples of Companies and Products

Several companies are active in the supplement strip market. Wellbeing Nutrition (melts®), DISO, Setu, Calmour, Solves Strips®, Unisom (melatonin), and NuStrips offer various consumer products. 

STIM Energy Strips is a new entrant touting to be the first in the world to use time release caffeine, promising to mitigate jitters and crashes. Manufacturers like Aavishkar (ThinSol® technology), ODF Nutra, and Makers Nutrition (private label) support the industry's growth. This mix of specialized manufacturers and consumer brands indicates a dynamic market.

Consumer Benefits and Drawbacks

Benefits

Consumers appreciate supplement strips for several reasons. Convenience and portability are major advantages for busy lifestyles. Faster absorption can mean quicker effects for energy or sleep supplements. Ease of use benefits those who dislike pills. Potentially better bioavailability might lead to more effective results. Pleasant tastes improve the daily routine of taking supplements. Some find strips cause less stomach irritation than pills. The discreet nature allows consumption anywhere.

Drawbacks

Consumers should also consider potential downsides. Strips can be more expensive than traditional pills. The limited dose per strip might not suit everyone's needs. Taste masking isn't always perfect, and some might dislike the flavor or texture. The need for careful storage due to moisture sensitivity can be inconvenient. The variety of supplements available as strips is still smaller than for pills. Not all supplement ingredients are suitable for strip formulation.

Bioavailability and Efficacy Studies

Research suggests oral dissolving strips can improve supplement bioavailability compared to standard pills. Absorption through the mouth lining avoids the harsh stomach environment and initial liver breakdown. Studies on specific drugs delivered via strips show rapid release and sometimes faster absorption rates than tablets. Some brands claim significantly higher bioavailability due to their technology. However, actual results depend on the specific supplement, formulation, and individual factors. More extensive clinical research is needed for definitive comparisons across various supplements.

Manufacturing Processes and Formulation

Common Manufacturing Techniques

Several methods are used to make strips. Solvent casting involves dissolving ingredients in a solvent, casting the solution, and evaporating the solvent. Hot-melt extrusion mixes melted ingredients and pushes them through a die to form a film. Other methods include semi-solid casting, solid dispersion extrusion, rolling, and freeze-drying (lyophilization). The chosen method affects the strip's properties, like dissolution speed and ingredient uniformity. Solvent casting is often used for heat-sensitive ingredients, while hot-melt extrusion is solvent-free and can help with poorly soluble ingredients.

Key Formulation Components

Strip formulations include several key ingredients. Water-soluble polymers (like HPMC, pullulan) form the strip's structure and allow rapid dissolving. Plasticizers (like glycerol, PEG) add flexibility. Sweeteners and flavoring agents improve taste. Saliva stimulating agents (like citric acid) can speed up disintegration. Surfactants help wet and dissolve the film. Other components might include coloring agents, stabilizers, absorption enhancers, and superdisintegrants.

Specific Considerations for Supplements

Formulating supplements into strips requires specific attention. The active ingredient should ideally be stable in water/saliva and have a relatively low molecular weight. Techniques like micronization or solid dispersions might be needed for poorly soluble supplements. Encapsulation can protect sensitive ingredients like probiotics. Effective taste masking is crucial for consumer acceptance given that many supplements have strong flavors.

Future Trends and Innovations

Emerging Technologies

The field is constantly advancing. Integrating nanoparticles could enhance delivery. Moisture-resistant polymers might improve stability. Continuous manufacturing processes could lower costs. 3D printing offers possibilities for personalized dosing and complex strip designs. Mucoadhesive polymers could allow for targeted, sustained release in the mouth. Better taste masking technologies are always being developed. Multilayer films might allow combining previously incompatible ingredients.

STIM Energy Strips are the first in the world to include liposomal encapsulated, time release caffeine, allowing for the aforementioned sustained release of caffeine into the body. This promotes a more sustained energy boost, compared to sharp spikes and crashes often seen in other products.

9.2. Potential for Personalized Supplementation

Strips offer great potential for personalized nutrition. The ability to deliver precise doses makes tailoring supplements to individual needs feasible. Research is moving towards customized strips based on dietary requirements, lifestyle, or health status, leading to more effective supplementation.

Addressing Current Limitations

Ongoing research aims to overcome current limitations. Increasing the amount of supplement per strip is a key focus. Improving stability against moisture and temperature is another goal. Finding better ways to formulate poorly soluble supplements will expand the range of usable ingredients. Success in these areas will broaden the appeal and utility of oral dissolving strips.