Advances in Orodispersible Films: Transforming Drug Delivery for Pediatric and Geriatric Patients.

Orodispersible films (ODFs) are innovative thin polymeric strips designed to disintegrate rapidly when placed on the tongue, releasing the active pharmaceutical ingredient (API) for absorption either directly through the oral mucosa or indirectly via the gastrointestinal tract after swallowing. This dual absorption pathway results in a faster onset of therapeutic action compared with conventional solid oral dosage forms such as tablets or capsules.¹

The need for ODFs arises from widespread difficulties in swallowing, known as dysphagia, which significantly impact drug administration in vulnerable populations. Globally, approximately 15–20% of the elderly population and nearly 30–40% of children below 12 years suffer from swallowing-related issues. These patients often find it challenging, uncomfortable, or even impossible to ingest traditional solid dosage forms, leading to poor compliance and compromised therapeutic outcomes.²

Conventional alternatives, such as oral syrups, suspensions, or dispersible tablets, though designed to ease administration, present additional challenges. Syrups often face palatability issues due to the bitter taste of APIs, while suspensions pose a risk of choking in pediatric patients. Moreover, both liquid formulations are prone to inaccurate dosing, spillage, and require measuring devices, further complicating their use. Such limitations highlight the importance of patient-friendly innovations like ODFs, which eliminate the need for water, ensure uniform dosing, and enhance overall patient convenience.³

Fig 1. Administration routes of oral film

ODFs offer several clinical and pharmaceutical advantages:

• Rapid disintegration on contact with saliva ensures quicker drug release and absorption.
• Taste masking technologies embedded within the film matrix significantly improve patient acceptability, particularly for bitter APIs.
• Accurate dosing is achieved, unlike syrups and suspensions where underdosing or overdosing is common.⁴
• Enhanced portability and stability, as ODFs are lightweight, compact, and resistant to mechanical stress, making them ideal for on-the-go administration.

The potential of ODFs has expanded significantly with the integration of advanced pharmaceutical technologies. The use of nanocarriers (e.g., nanoparticles, liposomes, and micelles) incorporated into films has improved the solubility and bioavailability of poorly water-soluble drugs. The emergence of smart films embedded with sensors or designed for controlled release has opened avenues for personalized therapy. Furthermore, 3D printing technology has revolutionized ODF manufacturing by enabling the customization of drug dose, shape, size, and release profile according to patient needs.⁵

Beyond their established use in over-the-counter (OTC) medications such as anti-allergics, antiemetics, and analgesics, ODFs are now being investigated for chronic therapies (e.g., antihypertensives, antidiabetics), emergency medicines (e.g., pain relievers, cardiovascular drugs), and even vaccination platforms, especially for low-resource settings where cold-chain maintenance is challenging.

In summary, ODFs represent a next-generation oral drug delivery system that addresses the limitations of conventional formulations, improves patient compliance, and aligns with the principles of patient-centric healthcare. With continuous advancements in formulation design and manufacturing technologies, ODFs are expected to play a pivotal role in the future of therapeutics, particularly in pediatrics, geriatrics, and populations with special medical needs.⁶

2. ADVANTAGES OF ORODISPERSIBLE FILMS

Orodispersible films provide a wide range of clinical and pharmaceutical advantages that make them a superior alternative to conventional oral dosage forms. The most prominent benefit is their ease of administration. Because ODFs can be placed directly on the tongue and dissolve within seconds without the need for water, they are especially suitable for pediatric and geriatric patients, individuals suffering from dysphagia, and even bedridden patients who may find swallowing tablets or capsules difficult. This convenient mode of administration also proves useful in emergency situations or during travel, where water may not be readily available.⁷

Patient compliance is another key factor contributing to the growing popularity of ODFs. Children often resist taking conventional tablets due to their size or unpleasant taste, while elderly patients may fear choking. The thin, lightweight, and rapidly dissolving nature of ODFs makes them less intimidating and much more acceptable. This improved compliance directly enhances therapeutic effectiveness, as patients are more likely to adhere to prescribed treatment regimens.²⁷

The rapid onset of action offered by ODFs is another significant advantage. Once the film disintegrates on the tongue, the active pharmaceutical ingredient can either be absorbed directly through the oral mucosa or enter the gastrointestinal tract upon swallowing. In cases where mucosal absorption predominates, the drug bypasses first-pass metabolism in the liver, leading to a faster and sometimes more efficient therapeutic response. This characteristic makes ODFs particularly useful in managing conditions that require immediate relief, such as nausea, pain, migraines, or allergic reactions.⁸

In addition to patient convenience, ODFs ensure accuracy in dosing. Unlike syrups and suspensions, which are prone to measurement errors, spillage, or variability in the amount administered, ODFs provide a pre-measured, fixed dose of medication with every film. This enhances both the safety and reliability of therapy, reducing the risk of underdosing or overdosing, which is especially critical in pediatric and geriatric care.²⁶

Another important advantage is the improved stability of ODFs compared with liquid formulations. Liquid oral dosage forms are often susceptible to microbial contamination and chemical degradation, which can shorten their shelf life and compromise safety. ODFs, being solid in nature, encapsulate the drug within a polymeric film matrix that offers superior physicochemical stability and prolonged shelf life. This reduces the need for preservatives and ensures consistent drug performance during storage and use.⁹

Finally, ODFs effectively address palatability issues that commonly affect oral formulations. Many active pharmaceutical ingredients are inherently bitter or unpleasant in taste, which discourages patient adherence. ODFs can incorporate sweeteners, flavoring agents, and advanced taste-masking techniques, such as microencapsulation or complexation, to significantly improve their acceptability. This feature is particularly valuable in pediatric medicine, where taste often determines whether a child will willingly take the medication.¹⁰

Taken together, these attributes demonstrate that ODFs are not only a convenient alternative but also a clinically advantageous dosage form that enhances patient adherence, ensures accurate dosing, improves therapeutic outcomes, and addresses long-standing limitations of traditional oral formulations.²⁵

3. FORMULATION COMPONENTS

The successful development of orodispersible films relies heavily on the judicious selection of excipients, as each component contributes to the overall performance of the dosage form. Key formulation considerations include mechanical strength, disintegration time, stability of the incorporated drug, and, most importantly, patient acceptability.

At the core of ODFs are film-forming polymers, which provide the structural framework of the dosage form. These polymers are responsible for imparting flexibility, tensile strength, and the rapid disintegration property that defines ODFs. Hydroxypropyl methylcellulose (HPMC) is among the most widely employed polymers due to its excellent film-forming ability and compatibility with a variety of active pharmaceutical ingredients. Other commonly used materials include pullulan, which offers transparency and superior mechanical strength; polyvinyl alcohol (PVA), known for its elasticity and stability; and sodium alginate, a natural polymer that enhances film disintegration and biocompatibility.¹¹

To counter the inherent brittleness of polymeric films, plasticizers are incorporated into the formulation. These excipients reduce internal stress within the film matrix, thereby improving flexibility, elasticity, and handling during both manufacturing and patient use. Glycerol, polyethylene glycol (PEG), and propylene glycol are widely adopted plasticizers that ensure the films remain soft, resilient, and resistant to cracking under storage conditions.²³

The active pharmaceutical ingredient (API) is the central component of any ODF formulation. APIs may be incorporated in their conventional crystalline or amorphous form, but increasingly, advanced strategies are being used to overcome solubility and bioavailability challenges. Techniques such as nanoparticle incorporation, micelle entrapment, and drug–polymer complexation enhance drug dissolution and improve systemic absorption. Due to the inherent thinness of films, the drug loading capacity is usually limited to approximately 30 mg, making ODFs more suitable for potent molecules that require low doses.^12,30

Patient acceptability, particularly in pediatric and geriatric populations, is further enhanced by the inclusion of sweeteners and flavoring agents. These excipients mask the unpleasant or bitter taste of many APIs and provide a pleasant sensory experience. Commonly used sweeteners include sucrose, mannitol, aspartame, and xylitol, while fruit-based or mint flavors are frequently added to improve palatability and encourage compliance.¹³

Finally, saliva stimulants are often incorporated to promote rapid disintegration of the film. Agents such as citric acid, tartaric acid, and malic acid stimulate salivary flow, thereby accelerating the breakdown of the film matrix and facilitating faster drug release. In addition to their functional role, these excipients also contribute to the overall mouthfeel, ensuring that the patient perceives the dosage form as pleasant and easy to use.^28,29

In essence, the formulation of ODFs is a delicate balance of structural, functional, and sensory components. The careful integration of polymers, plasticizers, APIs, taste enhancers, and saliva stimulants ensures that the films not only meet pharmaceutical performance requirements but also align with the principles of patient-centric drug delivery.¹⁴

4. MANUFACTURING TECHNIQUES

Several methods have been developed for the production of ODFs, each with unique advantages and limitations.

• The solvent casting method is the most widely employed technique. It involves dissolving or dispersing the drug and excipients in a suitable solvent and casting the solution onto a flat surface for drying. This method ensures uniform drug distribution and scalability but requires complete removal of residual solvents.²²
• Hot-melt extrusion (HME) avoids the use of solvents by heating and extruding a mixture of drug and polymer. HME produces films with excellent mechanical strength and eliminates solvent-related toxicity. However, it is unsuitable for heat-sensitive drugs.
• Electrospinning utilizes high-voltage electric fields to generate nanofiber mats, which are collected as thin films. These films offer large surface areas, ultra-fast disintegration, and enhanced dissolution rates, though the technique is costly and requires specialized equipment.¹⁵
• 3D printing has recently emerged as a revolutionary approach, enabling the fabrication of personalized ODFs with precise control over drug dose, size, and geometry. This technology is particularly valuable in pediatric and geriatric medicine, where customized dosing is often required. Despite its potential, 3D printing remains limited to small-scale production due to high costs and technical challenges.^24,31

5. ADVANCES IN ODF TECHNOLOGY

Significant progress has been made in enhancing the therapeutic potential of ODFs. Integration of nanoformulations—including nanoparticles, liposomes, micelles, and nanocrystals—has improved the solubility and bioavailability of poorly water-soluble drugs. For example, liposomal ODFs have shown promise in oncology applications.¹⁶

The use of biodegradable and natural polymers, such as chitosan, pullulan, starch derivatives, and alginates, ensures safety, eco-friendliness, and suitability for pediatric and chronic therapies.^21,32

Multi-layer films allow the incorporation of different drugs or release profiles within a single film, enabling controlled release, sustained release, or combination therapies. A dual-layer ODF, for instance, may provide both immediate and prolonged drug action.

The development of smart films, incorporating biosensors or stimuli-responsive materials, represents a futuristic innovation. Such films may respond to physiological changes (e.g., pH or glucose levels) to release drugs on demand, offering exciting possibilities in personalized medicine.

3D-printed ODFs further enable patient-specific dosing based on age, body weight, or disease condition, thus expanding the scope of individualized therapy.^17,33

6. CLINICAL APPLICATIONS

The clinical relevance of ODFs extends across multiple therapeutic areas.

• In pediatrics, ODFs are particularly beneficial for children who have difficulty swallowing solid dosage forms. Common applications include antipyretics (e.g., paracetamol), antiemetics (e.g., ondansetron), and antiepileptics (e.g., clonazepam). The use of taste-masking and accurate dosing enhances compliance in this population.
• In geriatrics, ODFs address dysphagia and polypharmacy concerns, offering safe and convenient alternatives. Cardiovascular drugs such as amlodipine and enalapril, as well as CNS drugs like donepezil, have been successfully formulated as ODFs, improving adherence and reducing aspiration risks.^35,42
• For emergency use, ODFs provide rapid therapeutic action via buccal absorption. Drugs such as antihistamines, analgesics, and anti-migraine agents (e.g., rizatriptan, sumatriptan) have demonstrated effectiveness in acute conditions, providing relief without the need for water or swallowing.
• In chronic diseases, ODFs improve long-term adherence by combining portability, ease of administration, and palatability. Their use in psychiatric, neurological, cardiovascular, and endocrine disorders highlights their versatility.^18,34

Summary Table of ODFs