Tablets can have different shapes. The biconvex form is particularly common with tablets for ingestion. Tablets for medicinal use are classified as medicinal products; in any other health-related use they are classified as medical devices or dietary supplements. Tablets are also used in other areas.
Many active ingredients can be tabletted – some directly, i.e. without further processing of the powder or powder mixture – but most of them via the intermediate stage of the granulate. As a rule, additional excipients are required in addition to the actual active ingredient.
Sculpture “Milestones of Medicine” at the Berlin Walk of Ideas, left the Marie-Elisabeth-Lüders-Haus
In 1843 the Englishman William Brockedon applied for the patent for these and is thus regarded as the inventor. The first preparations produced consisted of sodium bicarbonate, sodium chloride and potassium chloride and were soon called “compress pills”. In 1862 the term “tablet” was introduced, which was used for Brockedonian type compresses, whereby pastilles were already known as such in the past. As a result, the company had the name “tabloid” protected.
This was a fusion of tablet and alkaloid and refers to comprates with highly effective drugs in concentrated form. Brockedon looked at the technology used to produce the tablet while preparing briquettes in brick and clay factories.
All these different tablets are produced in tablet presses.
Disadvantages of the tablets
If you take the tablets incorrectly, without sufficient liquid while taking them, they will not reach the stomach, but will stick to the oesophagus for a while. In some people, the tablets stick to the throat during the swallowing process, which causes unpleasant foreign body feelings.
Coarsely crystalline powders with cubic crystals are best processed. The powders should be dry, i.e. have a residual moisture of max. 10 % and be pressed in rooms with a maximum relative humidity of 50 %.
The addition of additives in the powder mixture improves the properties required for tableting and modifies the properties of the finished tablet.
Fillers are required for processing very small amounts of active ingredient. Fillers ensure that the tablet gets the necessary size/mass. Strengths and lactose are used.
Lubricants are divided into three subgroups
Superplasticizers improve the flow properties of the aggregate. This allows it to flow better into the die during tableting, thus also improving the dosing accuracy. They reduce interparticular friction. They reduce the moisture on the surface.
They reduce frictional and adhesive forces between the bulk material particles. Lubricants have the function of facilitating the ejection of the tablet from the die by reducing friction between the inner wall of the die bore and the side surface of the tablet. Mould release agents are designed to prevent the tablet mass from sticking to the punches and the inner wall of the die.