Pharmaceutical dosage forms can be defined by their appearance as much as (if not more than) their formulation. The shape of a dosage form has a significant impact on its function, manufacturability, and acceptance by patients.
The dosage form shape impacts many characteristics of the dosage form besides just aesthetics, including drug release, ease of swallowing, coating efficiency, identification, and packaging. Over the years, there have been many advances in pharmaceutical design and manufacturing that have led to many shapes for specific therapeutic, aesthetic, and handling uses.
The aim of this document is to provide an overview of the types of shapes used to create dosage forms, the rationale behind their design, and the effect they have on the patient's experience with a product as well as the performance of that product.
1. Compliance of Patients: The ease with which a patient can swallow a tablet or capsule is determined by the size and shape of that dosage form. Patients find rounded and oval shapes easier to swallow because they slide through the esophagus more effortlessly.
2. Identification and Differentiation: The use of color and imprint code, along with the shape of a product, can distinguish it from all other products and can help to eliminate medication error.
3. Efficiency of Manufacturing: Some dosage form shapes will lend themselves to easier compression, coating, and packaging in mass production than other shapes.
4. Drug Release Characteristics: For some modified-release and controlled-release formulations, the actual shape will have a significant impact on the desired surface area-to-volume ratio.
5. Branding: Some pharmaceutical manufacturers will use unique shapes for their dosage form as part of their branding strategy. This will assist in the recognition of the manufacturer's product by the patient.
Advantages:
- easy to manufacture and inexpensive
- uniform compressive force distribution around the tablet during the tabletting process
- easier to coat and uniformly dry.
Common Uses:
Plain tablets, chewable tablets and effervescent tablets.
Example: Paracetamol 500 mg tablets are generally round, and have a biconvex shape, which makes swallowing the tablet easy.
Advantages:
- Oval Tablets are easier to swallow than round tablets that have the same weight.
- Ideal shape for tablets coated with film or enteric film
- Preferred visually by the patients.
Example: Amoxicillin and Ibuprfen are usually in an oval shape for patient compliance.
Advantages:
Advantages:
Advantages:
Advantages:
Advantages:
Advantages:
Advantages:
Advantages:
Advantages:
Examples include:
- Tubes (ointment/gel) are designed as cylindrical containers with squeezable bodies to facilitate accurate dosage dispensing.
- Ampoules or vials are designed as cylindrical containers to ensure uniform heating of the contents during sterilization.
- Bottles of syrup and suspension are rounded both to allow for easy dispensing of the contents and to provide for printed labels.
Other recent designs have also included unit-dose sachets and prefilled syringes that have been designed to promote convenience, safety, and accurate dosage.
Examples: Metformin and glibenclamide utilize bilayer tablets to deliver diabetes treatments.
Example: Nifedipine OROS is an example of an osmotic pump tablet.
Example: Spritam® - a porous 3D-printed structure utilizes a porous structure for rapid disintegration of levetiracetam tablets.
- The properties of the drug: solubility, stability and dose size
- The method of manufacture: either compression, coating and/or encapsulation
- The target population for the drug: pediatric patients, geriatric patients or patients with special needs
- The regulations of an individual country, in addition to branding issues (differentiating from competitors)
In effect, the ultimate design of the dosage form's shape should achieve a good balance between optimal performance and patient experience.
Now that we are in an age of "precision medicine" and "patient-specific therapies," dosage form designs will continue to evolve through the application of advanced materials, automation, and data analytics to create medicines that are not only safe and effective but also user-friendly.
Ultimately, a well-designed dosage form, whether it is how it is made or its shape, will lead to increased patient adherence to taking their medications, improved patient outcomes, and increased patient confidence in their medication and in the pharmaceutical industry.
The aim of this document is to provide an overview of the types of shapes used to create dosage forms, the rationale behind their design, and the effect they have on the patient's experience with a product as well as the performance of that product.
Importance of the Shapes of Dosage Forms
A discussion of dosage form shapes would not be complete unless you understand why shape is important.1. Compliance of Patients: The ease with which a patient can swallow a tablet or capsule is determined by the size and shape of that dosage form. Patients find rounded and oval shapes easier to swallow because they slide through the esophagus more effortlessly.
2. Identification and Differentiation: The use of color and imprint code, along with the shape of a product, can distinguish it from all other products and can help to eliminate medication error.
3. Efficiency of Manufacturing: Some dosage form shapes will lend themselves to easier compression, coating, and packaging in mass production than other shapes.
4. Drug Release Characteristics: For some modified-release and controlled-release formulations, the actual shape will have a significant impact on the desired surface area-to-volume ratio.
5. Branding: Some pharmaceutical manufacturers will use unique shapes for their dosage form as part of their branding strategy. This will assist in the recognition of the manufacturer's product by the patient.
Most Common Shapes of Solid Dosage Forms
There are more than 70% of all pharmaceutical products available as solid dosage forms of medicine, such as tablets and capsules. The shape of these solid dosage forms vary greatly in relation to functionality, visual appeal, and mechanical properties.1. Round (Circular) Tablets
Round tablets are the most commonly used shape for tablets because they have been used traditionally, and they are the most common form of tablets.Advantages:
- easy to manufacture and inexpensive
- uniform compressive force distribution around the tablet during the tabletting process
- easier to coat and uniformly dry.
Common Uses:
Plain tablets, chewable tablets and effervescent tablets.
Example: Paracetamol 500 mg tablets are generally round, and have a biconvex shape, which makes swallowing the tablet easy.
2. Oval or Elliptical Tablets
Oval shaped tablets are referred to as elongated ovals with curved edges that form a smooth curve.Advantages:
- Oval Tablets are easier to swallow than round tablets that have the same weight.
- Ideal shape for tablets coated with film or enteric film
- Preferred visually by the patients.
Example: Amoxicillin and Ibuprfen are usually in an oval shape for patient compliance.
3. Caplet (Capsule-Shaped Tablet)
Caplets are oval and elongated shaped hybrid forms of both capsules as well as tablets; with non-abrasive surfaces.Advantages:
- Combines the ease of swallowing of a capsule with the strength of a tablet.
- Minimizes dusting and chipping during the coating and packaging of a caplet.
- Usually used for coated formulations, as they are typically designed so taste does not affect use or performance.
4. Oblong Tablets
Oblong or rectangular shaped tablets that have rounded edges.Advantages:
- Are good for containing high doses in an individual tablet.
- Provide a large surface area for coating or printing.
- Provides unique differentiation as a product.
5. Square and Rectangular Tablets
Square/rectangular shaped tablets that have defined corners/edges.Advantages:
- Provides unique brand identification.
- Good for chewable/dispersible formulations as they do not need to be swallowed.
- Difficult to swallow due to sharp corners/edges.
- Could easily chip during the coating process.
6. Triangular & Diamond-Shaped Tablets
Tablets with a unique shape for branding & identification purposes.Advantages:
- Reduced potential for accidental mix-up with other drugs.
- Strong visual identification for patient.
7. Heart Shaped Tablets
Heart-shaped tablets are aesthetically and/or symbolically designed for cardiovascular/well-being.Advantages:
- Presents an emotional connection for use in specific types of therapies (e.g. Heart health).
- Easily marketed and recognized.
8. Cylindrical and Barrel-Shaped Tablets
Description: These tablets are a short cylinder or barrel shape and have been primarily used in effervescent or chewed forms.Advantages:
- Provide greater surface area for quick disintegration.
- Can accommodate larger dosages.
Capsule Shapes and Their Variations
There are different types of shape for capsules (both soft gel and hard gel) based on what you are going to put in them and how much (dose or dosage).1. Cylindrical Capsules
The standard capsule is made up of two pieces-sized and smooth; body and cap make up a smooth cylinder.Advantages:
- Capsules are simple and effective for the filling of powders or granules.
- Capsule surfaces make it easy for individuals to swallow them.
2. Oblong shaped Capsules
Oblong capsules are designed to be extended in length to accommodate a higher fill volume or a combination of multiple drug solutions.Advantages:
- Oblong shapes allow for an increased amount of material without the outside diameter increasing at all.
- Capsule designs can be either sustained or controlled release.
3. Pearl or Spherical Capsules
Pearl shaped/spherical soft gel capsules vary in size (generally very small), are shiny/glossy, tears filled, have a smooth texture, and are very pleasing to the eye.Advantages:
- Are visually appealing and have a smooth surface.
- Are very easy to swallow by children and by elderly people.
Shapes of Semi-Solid and Liquid Forms of Dosage
Unlike tablets, semi-solid and liquid dosage forms do not have permanent defined geometric shapes; however, designs of containers and delivery systems can impact both the usability and the accuracy of the dosage administration.Examples include:
- Tubes (ointment/gel) are designed as cylindrical containers with squeezable bodies to facilitate accurate dosage dispensing.
- Ampoules or vials are designed as cylindrical containers to ensure uniform heating of the contents during sterilization.
- Bottles of syrup and suspension are rounded both to allow for easy dispensing of the contents and to provide for printed labels.
Other recent designs have also included unit-dose sachets and prefilled syringes that have been designed to promote convenience, safety, and accurate dosage.
New Shapes for Drug Dosage Forms
The rapid growth of pharmaceutical technology has resulted in many new shapes for dosage forms that meet a wide range of specialized needs.A. Multifunctional Tablets
Examples of multiple multifunctional tablets would be bilayer, trilayer, and donut-shaped tablets that provide multiple active ingredients for delivery in one dosage form while also controlling release rates.Examples: Metformin and glibenclamide utilize bilayer tablets to deliver diabetes treatments.
B. Osmotic Pump Tablets (representative shape is round with an orifice)
Osmotic pump tablets utilize a small laser-drilled hole to control the release rate of the drug via osmotic pressure.Example: Nifedipine OROS is an example of an osmotic pump tablet.
C. Tablets Manufactured Using 3D Printing Technology
Additive manufacturing allows the creation of very complex shapes for tablets that provide optimal dissolution characteristics or meet the individual needs of a particular patient.Example: Spritam® - a porous 3D-printed structure utilizes a porous structure for rapid disintegration of levetiracetam tablets.
Factors Influencing Shape Selection
The selection of a dosage form's shape is determined by balancing functionality and mechanics against patient needs, as well as the performance of the dosage form itself. Functional factors include:- The properties of the drug: solubility, stability and dose size
- The method of manufacture: either compression, coating and/or encapsulation
- The target population for the drug: pediatric patients, geriatric patients or patients with special needs
- The regulations of an individual country, in addition to branding issues (differentiating from competitors)
In effect, the ultimate design of the dosage form's shape should achieve a good balance between optimal performance and patient experience.
The Role of Shape in Quality Control and Packaging
- The shape of tablet or capsule plays an important role within the area of Quality Control (QC) and Packaging. QC inspection systems use shape recognition technologies to identify broken or misshapen tablets/capsules.
- Packaging design (e.g., blister cavities or capsule trays) can be custom-designed to accommodate unique shapes.
- In terms of uniformity of shape, the shape of a tablet/capsule also has an impact on significant quality attributes such as (i) hardness of the tablet/capsule, (ii) consistency of the coating on the tablet/capsule and (iii) dissolution rates of the tablet/capsule.
Now that we are in an age of "precision medicine" and "patient-specific therapies," dosage form designs will continue to evolve through the application of advanced materials, automation, and data analytics to create medicines that are not only safe and effective but also user-friendly.
Ultimately, a well-designed dosage form, whether it is how it is made or its shape, will lead to increased patient adherence to taking their medications, improved patient outcomes, and increased patient confidence in their medication and in the pharmaceutical industry.
No comments:
Post a Comment
Please don't spam. Comments having links would not be published.