In the pharmaceutical industry, prioritising product control, patient safety, and adherence to standards are crucial. This responsibility extends to maintaining the quality of solid dosage forms which are frequently utilised in veterinary medicine.
A tablet used in animal health consists of one or more active ingredients and numerous excipients and may be a conventional tablet that is swallowed whole a chewable tablet, or a modified-release. Conventional and chewable tablets are used to administer drugs to dogs and cats, whereas modified-release boluses are administered to cattle, sheep, and goats. Tablets offer advantages in terms of physical and chemical stability compared to liquid dosage forms.1
Ensuring the quality and effectiveness of tablets in veterinary medicine is of utmost importance. However, several challenges can occur during manufacturing that may affect this, with the most common hurdle being sticking. Sticking issues can compromise the tablet’s appearance, structural integrity, and dissolution properties, potentially affecting the delivery and efficacy of the medication.
Sticking occurs when granules build up on the punch-tip face of the tablet tooling. This issue is not only problematic for human tablets but also those used for animals and can result in considerable tablet press downtime and unpredictable production delays. Ensuring consistent tablet quality is vital for consistent mass production of quality tablets.
A Common Problem
So, why is sticking so common? The answer lies in several factors, including the formulation’s physicochemical properties and the punch face’s surface characteristics. These factors can be particularly challenging to manage when formulating tablets for animals, as their specific health requirements and dosage needs must be taken into account.
Fortunately, advancements in tabletting science have helped to find solutions to address sticking issues during tablet manufacturing. When these solutions are applied, they can dramatically improve production efficiency and tablet quality. It is important to prioritise proper quality control measures and adhere to dosage requirements in order to ensure the safety of animal medications. Minimising problems such as sticking during the tablet manufacturing process plays a vital role in achieving these objectives.
Distinguishing Picking from Sticking
Sticking can sometimes be confused with another common problem encountered during tablet production – picking. Picking is when the formulation becomes trapped in the embossing or design feature, leaving the finished product with visibly poor definition. Various approaches can be employed to address picking, with product design alterations such as the inclusion of embossed counters and tapered features.
To reduce picking, font styles should be designed with large open counters and no sharp corners where granules can become trapped. Additionally, the right font style can also help avoid coating problems, tooling failures, and lack of distinction.
Open islands or counters are highly susceptible to picking, and granules can easily become trapped in these areas on the face of the punch tip. To minimise this issue, the counter should be modified by reducing the depth of the stroke, thereby increasing the surface area and minimising the likelihood of picking.
Another effective approach is the use of tapered peninsulas, which involve enhancing the corner radii in sharp, compound angles of the embossing detail. This tapered design blends the tablet face’s surface with the stroke angle, resulting in a softer profile and reducing the risk of powder entrapment. By employing this method, the definition can be maintained without compromising the overall stroke depth of the embossing, and ultimately helping to preserve a clear brand identity.