The tablet – an interesting galenic form for food supplements

There are many reasons why the tablet is indisputably the most important dosage form. Most raw materials container be processed into tablets - sometimes after appropriate pre-processing - and production container be easily automated and is therefore cost-effective for large quantities. The dosage container be controlled and stability is also guaranteed over a longer, market-standard period of time if stored appropriately. The safe and convenient application is also seen as an advantage. The consumer container easily carry the tablet with them and take it discreetly and on time. The different sizes and the attractive appearance help the consumer to distinguish different products or dosages from one another. The pleasing shape and the break resistance contribute to the fact that the tablets container be well packaged and are therefore easy to transport.^[3].

The widely practiced method of enveloping drugs in dough-like food was already used in Egypt around 1500 BC. Pastilles, pills and other shaped, solid variants are to be seen as the immediate predecessors of the tablet. Like the Egyptians, the Greeks in ancient times also prepared pellets from unpleasant-tasting active ingredients. The invention of the manual tablet press by Brockedon in 1843 brought about a change in the field of solid oral dosage forms. Tablet production on an industrial scale in Europe was promoted in 1884 by the company Burroughs Wellcome & Co. in London. They had the term "tabloid" protected as a brand name and subsequently produced considerable quantities.^[1].

The quote by Robert C. White from 1920, "The life of the tablet maker is not a happy one," is very apt here, as the demands on this technologically very complex process are very high. The production of a so-called tablet is explained in more detail below.

The already mixed powder mass prepared for tableting is pressed into a tablet using very high pressure. Hand presses container be used for initial tests to determine the compressibility of a powder or powder mixture. Eccentric presses or small rotary presses are used for further tests on a development scale. The difference between an eccentric and a rotary press in the broadest sense is that the eccentric press is a one-sided press and the rotary press is a two-sided press. However, both technologies are based on the same basic principle. A die is filled with the mixture to be tableted and pressed into a tablet by two punches. The rotary machines are, however, much more powerful than eccentric presses because they contain a much larger number of tool sets (die, upper and lower punches) and container therefore produce a larger quantity of tablets.^{[1, 3]}.

A large number of active ingredients container be tableted, some of them directly, i.e. without further processing of the powder. There are so-called DC materials (DC = Direct Compression). In most cases, however, in addition to the actual active ingredient, additional excipients are required to produce a technologically optimal tablet. Excipients in a tablet are all components that are not responsible for a nutritional or physiological effect in the body. These include fillers such as lactose, microcrystalline cellulose, starches and many more, which are required when processing very small amounts of active ingredients. Croscarmellose sodium or modified starch is often used as a disintegrant. Magnesium stearate is most commonly used as a lubricontainert, which improves the flow properties of the powder mixture and prevents the tablet mass from sticking to the stamps. So-called "compound excipients" are excipients that are made from a mixture of different substances, for example microcrystalline cellulose with calcium phosphate.^{[1, 3]}.

The in-process controls that should be carried out during state-of-the-art tablet production, including for food supplements, include hardness measurement, checking the tablet weight, abrasion, tablet height and disintegration time.

There are a variety of tablet shapes. Starting with the round, double-sided, biconvex tablet, through an oval to an oblong variant, which are probably the most common shapes. The market also offers square tablets or tablets in the shape of a heart or half moon, as well as many other variations. The size of the tablets ranges from a 2 to 3 mm micro tablet to large effervescent tablets or glucose tablets with a diameter of 25 mm. Embossing or engraving is also possible for tablets, which are incorporated into the tablet stamps and thus the corresponding tablet image is automatically created in one step during the pressing process. Such lettering or logos support recognition and thus branding for a product. The insertion of break notches is also possible if the tablet is intended to be divisible.^{[4, 5]}.

Tablets for oral use are divided into uncoated tablets, coated tablets, tablets with a modified release behaviour, gastro-resistant tablets, chewable tablets, sublingual tablets (for absorption of the active ingredient via the oral mucosa) and some more.^[4]. The chewable tablet is a very convenient form. You container take it at any time, no matter where you are, without needing a glass of water. Similar to Sticks With powder that container be taken directly, the chewable tablet has also been developed for a modern, dynamic and spontaneous lifestyle. Even larger chewable tablets are completely problem-free to consume because the chewable tablets do not have to be swallowed whole - unlike normal tablets. The chewable tablet is especially suitable for children or older people who containernot or do not want to swallow normal tablets.

The coated tablet is a special type of tablet. The coating or filming (also Coating Coating of tablets is an important process step, among other things to protect against environmental influences, which actually has its origins in pharmaceutical production. The demand for coated products in the field of food supplements is constantly increasing. An additional coating of the tablet is used for stability reasons, because the active ingredients are often sensitive to moisture, oxygen or light. With this additional protection, a chemical change in the active ingredients and their possible inactivation container be prevented.

A delayed release or even gastro-resistant protection (also called enteric coating) is also possible through film coating. In addition to tablets, Soft capsules The requirements for the tablet to be coated are low porosity, low friability, ie low abrasion of the tablet under mechanical stress, and a certain tablet hardness^[6].

A colored one filming of tablet cores not only serves aesthetic purposes, but also makes it easier to identify the respective food supplement. Both natural and synthetic dyes are possible here. A coating also makes it easier to swallow or achieves a more pleasant mouthfeel by masking the taste and smell of an ingredient. It promotes the consumer's positive attitude towards the food supplement or medicine through a high recognition value. This applies in particular to colored and flavored film coatings, which ultimately also support the branding of the product. This provides a high recognition value and has a positive effect on compliance, i.e. the regular consumption of the food supplement. Coated tablets are also often more resistant to mechanical influences than uncoated tablets. In addition, the additional coating provides a certain barrier against product counterfeiting^{[6, 7]}.

Legal considerations must not be ignored when it comes to food supplements. For example, each country has its own regulations on which excipients container be added to a tablet and in what quantities. Countries often base their regulations on the European, Americontainer or Japanese pharmacopoeia. In Japan, for example, there are quantity limits for various excipients such as hydroxypropylmethylcellulose (HPMC) and corn starch.^[7]This means that the selected excipients container be classified as medicinal products in some countries and as food supplements in others. The excipient composition of microcrystalline cellulose (MCC) (E 460), colloidal silicon dioxide (E 551), carboxymethyl starch sodium and sodium stearyl fumarate is not approved for food supplements because the latter two excipients may only be used for medicinal products. Instead, croscarmellose (E 468) and diacetyl tartaric acid esters of mono- and diglycerides of fatty acids (E 472e) are added to the MCC and colloidal silicon dioxide and made food-compliant.^[8]Here, only the additive E 472e has a set ADI (acceptable daily intake) value of 50 mg/kg, which must be observed. All other excipients have no set maximum amount. Information on approval is frequently changed, so it should be checked regularly for its currentness and validity.^[9].

After production and before the next processing step (coating or packaging), the tablets are first cleaned of technically unavoidable surface dust in a so-called tablet dust remover. This is the only way to ensure that subsequent processing steps (e.g. coating) and the Packaging run smoothly ^[10]The tablets container then be used, for example, in blister packaging or containerned.

A lot of theoretical knowledge is required for tablet production. However, this is not enough and a lot of practical experience is needed to develop a certain intuition in order to produce tablets for the consumer that are technologically optimal and reproducible in exactly the same quality in each subsequent production run. ^[1]. In a pilot plant, it is possible to develop the optimal formulation through initial compression tests on a small rotary press. Developing a food supplement tablet is always a challenge, as the range of excipients permitted in the food sector is much more limited than in the pharmaceutical sector. Our manufacturers of the various tableting excipients are continually working to improve the excipients and modify their properties so that, in turn, the tablet becomes even better and is even easier to produce.