Вспомогательные вещества в лекарственных препаратах

Substance formulated alongside the active ingredient of a medication

Excipient is a substance formulated alongside the active ingredient of a medication. Excipients serve various purposes, including long term stabilization, bulking up solid formulations containing potent active ingredients in small amounts (often referred to as "bulking agents", "fillers", or "diluents"), or enhancing the therapeutic properties of the active ingredient in the final dosage form. They can facilitate drug absorption, reduce viscosity, or enhance solubility. Excipients can also aid in the manufacturing process by improving the handling of active substances, facilitating powder flowability, or preventing denaturation and aggregation during the expected shelf life. The selection of excipients depends on factors such as the route of administration, dosage form, and active ingredient. Pharmaceutical regulations and standards mandate the identification and safety assessment of all ingredients in drugs, including their chemical decomposition products. It is common for a final drug formulation to contain more excipient than active ingredient, and virtually all marketed drugs contain excipients. In some cases, novel excipients can be patented, while in others, the specific formulation involving them is kept as a trade secret to prevent reverse engineering.

Though excipients were at one time assumed to be "inactive" ingredients, it is now understood that they can sometimes be "a key determinant of dosage form performance"; Such studies are called excipient controlled or vehicle controlled studies.

Adjuvants are added to vaccines to enhance or modify the immune system response to an immunization. An adjuvant may stimulate the immune system to respond more vigorously to a vaccine, which leads to more robust immunity in the recipient.

Antiadherents reduce the adhesion between the powder (granules) and the punch faces and thus prevent sticking to tablet punches by offering a non stick surface. They are also used to help protect tablets from sticking. The most commonly used is magnesium stearate.

Tablet coatings protect tablet ingredients from deterioration by moisture in the air and make large or unpleasant tasting tablets easier to swallow. For most coated tablets, a cellulose ether hydroxypropyl methylcellulose (HPMC) film coating is used which is free of sugar and potential allergens. Occasionally, other coating materials are used, for example synthetic polymers, shellac, corn protein zein or other polysaccharides. Capsules are coated with gelatin. Enterics control the rate of drug release and determine where the drug will be released in the digestive tract. Materials used for enteric coatings include fatty acids, waxes, shellac, plastics, and plant fibers.

Colours are added to improve the appearance of a formulation. Colour consistency is important as it allows easy identification of a medication. Furthermore, colours often improve the aesthetic look and feel of medications. Small amounts of colouring agents are easily processed by the body, although rare reactions are known, notably to tartrazine. Commonly, titanium oxide is used as a colouring agent to produce the popular opaque colours along with azo dyes for other colors. By increasing these organoleptic properties a patient is more likely to adhere to their schedule and therapeutic objectives will also have a better outcome for the patient especially children.

Sorbents are used for tablet/capsule moisture proofing by limited fluid sorbing (taking up of a liquid or a gas either by adsorption or by absorption) in a dry state. For example, desiccants absorb water, drying out (desiccating) the surrounding materials.

Sweeteners are added to make the ingredients more palatable, especially in chewable tablets such as antacid or liquids like cough syrup. Sugar can be used to mask unpleasant tastes or smells, but artificial sweeteners tend to be preferred, as natural ones tend to cause tooth decay.