Caleva – Pharmaceutical Granulation


Sep 5, 2012
What’s in my tablet? – A quick guide on Pharmaceutical Granulation. Medical tablets are consumed on a significantly large scale across the world every single day. They are one of the most widespread forms of medication for a large range of illnesses and diseases, from the common cold to much more serious and sometimes life threatening conditions. Having been widely accepted as being trustworthy and effective, it is uncommon for consumers to question what each pill contains or how it was made. However for those of you that may have a small sense of curiosity towards this form of pharmaceutical delivery system, here is a little insight into the formation of medical tablets through the process of pharmaceutical granulation. The Ingredients Two key ingredients must be combined in order to create an effective tablet. The first of these is the active ingredient: the drug itself which when released around the body will treat the consumer’s condition. The second ingredient is an inert substance which enables even distribution of the active ingredient around the body and adds bulk to the tablet, called an excipient. Both of these substances are originally sourced as two separate powders, however when mixed and moulded into the tablets we see today, they work coherently to provide efficient treatment. Medical companies often also add a coating to improve the taste for consumers. The two powders alone can have an unappealing chemical taste therefore making them highly off-putting for the user. Coatings often contain sugar to create a sweeter, more enjoyable taste. This coating can also be used to manipulate the release of the active ingredient alongside the excipient ingredient. Alternatively, some producers choose to simply add a flavoured inert substance to the tablet itself in an attempt to improve taste. The type of excipient substance used is carefully considered to enhance the efficiency of the drug and prevent any dangerous reactions between the two ingredients. Different types include; binders (e.g. saccharides or proteins), preservatives (e.g. antioxidants or citric acid), glidants (e.g. talc or magnesium carbonate), anti-adherents (e.g. magnesium stearate), fillers (e.g. lactose or calcium carbonate) and lubricants (e.g. vegetable fats) among many others. Producers are required to cautiously calculate and test the amount of each ingredient along with the ratio of active to inert substance before production to ensure the best possible results. This helps to minimise any harmful side effects that could occur. The process There are variations in the process of pharmaceutical granulation for different types of tablets depending on the density or size along with the ingredients used. During all processes however, the powder particles of each ingredient are collated to form granules. Bonds are formed within each granule through compression or the use of a binding agent. There are two main types of pharmaceutical granulation currently employed. One of which is wet granulation whereby a granulation liquid is added to the powder bed of the granulator. The liquid added can include water, ethanol, isopropanol or a mixture of the three, however once the granules have been formed, it will be removed through a drying process. In the traditional wet granulation processes, the wet mixture will be pressed through a sieve-like utensil to create the granules. The second type is dry granulation. This process will be employed where ingredients are sensitive to heat or moisture. Within dry pharmaceutical granulation, there is a particular focus on the compacting and densification of the powders within high pressure containments to ensure binding occurs. It is important to guarantee that the two ingredients are correctly blended during this process to prevent segregation. If segregation of the two ingredients does occur, tablets can either not work efficiently, or sometimes cause negative and harmful reactions of varying degrees when consumed. This can often be avoided through granulating the active ingredient alone in the first instance, before granulating the two ingredients together as a second stage. Profuse testing of all products takes place before large scale production occurs. For more information visit –