What's in a medicine?

@HealthMed Most of the weight of a tablet or capsule consists of coatings and fillers to make the enclosed active ingredient is big enough to pick up. Some common medicines such as the heart tablet digoxin or thyroid replacement treatment may have an active ingredient weight of as low as one tenth of a gram - ie it might take around 50 doses to fill a level teaspoon.
That raises the obvious question: what other ingredients are present in medicines? The range of fillers includes usually harmless chemicals such as the sugar lactose. That could prove a problem with patients who suffer lactose intolerance - due to immaturity in or loss of the enzyme needed to break down lactose.
And liquids or tablet coatings may include animal extracts, in the form of gelatin. Although this should be clearly labelled on the package insert that should accompany all medicines, a paper in the latest issue of the Postgraduate Medical Journal has reported that many patients on restricted diets are unaware of this.
The study in the Postgraduate Medical Journal reported that a quarter of patients surveyed who were on restricted diets were unaware that they had been prescribed drugs containing gelatin, contrary to their wishes or beliefs as vegetarians, or for other cultural or religious reasons.
If not clear from the packaging, patients should ask their pharmacist for further information on the non-drug contents of medicines prescribed, or bought over the counter without a prescription.

See BBC report on the PMJ article