Definition
On the one hand, drugs contain the active ingredients that mediate the pharmacological effects. On the other hand, they consist of excipients, which are used for the production or to support and regulate the drug effect. Placebos, which consist only of excipients and contain no active ingredients, are an exception. Excipients can be of natural, semi-synthetic and synthetic (artificial) origin. They should be atoxic and microbially safe. Compatibility with the containers, with the other excipients and with the active ingredients is also important. Their share in terms of number and quantity is usually higher than that of the active ingredients. Very rarely, finished drugs do not contain excipients – an example is the anesthetic sevoflurane, which consists only of the active ingredient.
Features
Excipients perform a variety of functions in drugs. They are important for shelf life, stability, shaping, weight, consistency, taste, appearance, promotion of release, absorption and bioavailability, pH and osmolarity adjustment, protection, and the manufacturing process. Excipients were traditionally considered pharmacologically inert. However, they are important for both pharmacodynamics and pharmacokinetics and may also be active themselves in some circumstances (e.g., ointment bases, essential oils). Excipients can be considered problem solvers. For example, water rapidly becomes microbially contaminated. So preservatives are added to the preparation. Or fat-soluble substances dissolve poorly – an emulsifier mediates between the hydrophilic and lipophilic phases.
Relationship to food
Most pharmaceutical excipients are also used in the preparation of processed foods – as food additives. Therefore, they may also be assigned an E number.
Mandatory declaration
Since January 1, 2019, the so-called full declaration of excipients applies in many countries. All excipients contained must be listed in both the technical and patient information (Arzneimittel-Zulassungsverordnung, AMZV).
Groups
The following list shows a selection of excipient groups for drug manufacture. A detailed list of excipients can be found at the end of this article.
- Antioxidants
- Flavorings
- Binder
- Emulsifiers
- Dyestuffs
- Film former
- Filler
- Gel former
- Flavor correctors
- Complexing agents
- Preservative
- Solvent
- Solubilizer
- Buffer
- Ointment bases
- Acidifier
- Acidity regulators
- Acids and bases
- Lubricants
- Sweetener
- Coating agent
- Thickening agent
- Disintegrant
Adverse effects
Some excipients can cause adverse effects. For example, the parabens, lanolin and peanut oil can cause allergic reactions. Sweeteners and colorants have been criticized for various reasons. Aluminum compounds have also been suspected of being harmful to health for several years. Additives such as lactose, mannitol, gluten, sorbitol and fructose can trigger gastrointestinal disorders in sensitive people. Benzalkonium chloride may cause discoloration of contact lenses and butylated hydroxyanisole may irritate the skin. Some excipients are controversial because of their origin, such as gelatin, which is derived from animals, or petroleum products such as petrolatum and kerosenes, which are not sustainable. Palm oil is also criticized for ecological reasons. Sugar can damage teeth and alcohol triggers central nervous disorders. The antioxidant sodium metabisulfite is contained in injection solutions with epinephrine for the treatment of severe allergic reactions. However, it can also cause allergies itself.
List of excipients in drugs (selection).
A
- Acesulfame K
- Acetone
- Malic acid
- Agar
- Albumin
- Alginates
- Alginic acid
- Aluminum hydroxide
- Alumina
- Aluminum phosphate
- Aluminum stearate
- Ammonia
- Ammonium alginate
- Arabic gum
- Ascorbic acid
- Ascorbyl palmitate
- Aspartame
- Attapulgit
B
- Bentonite
- Benzalkonium chloride
- Benzethonium chloride
- Benzoate
- Benzoic acid
- Benzyl alcohol
- Benzyl benzoate
- Beeswax
- Boric acid
- Butylated hydroxyanisole
- Butylhydroxytoluene
- Butylparaben
C
- Calcium alginate
- Calcium carbonate
- Calcium hydrogen phosphate
- Calcium stearate
- Carrageenan
- Carbomers
- Carmellose
- Carnauba wax
- Cellulose acetate
- Cellulose acetate butyrate
- Cellulose acetate phthalate
- Cellulose
- Cellulose powder
- Cetrimide
- Cetyl alcohol
- Cetylpyridinium chloride
- Cetylstearyl alcohol
- Chitosan
- Chlorhexidine
- Chlorobutanol
- Chlorocresol
- Chlorxylenol
- Cholesterol
- Copovidone
- Cresol
- Croscarmellose sodium
- Crospovidone
- Cyclamate
- Cyclodextrine
- Cyclomethicone
D
- Denatonium benzoate
- Dextrane
- Dextrins
- Viscous kerosene
- Diethanolamine
- Diethyl phthalate
- Difluoroethane
- Dimethicone
- Dimethylacetamide
- Dimethyl ether
- Dimethyl phthalate
- Dimethyl sulfoxide
- Disaccharide
- Docusate sodium
- Thin kerosene
E
- EDTA
- Iron oxides
- Enzymes
- Peanut oil
- Erythritol
- Acetic acid
- Ethanol
- Ethyl 4-hydroxybenzoate
- Ethyl acetate
- Ethyl cellulose
- Ethyl lactate
- Ethyl maltol
- Ethyl oleate
- Ethylparaben
- Ethylvanillin
F
- Dyes
- Fats
- Fatty acids
- Fructose
- Fumaric acid
G
- Galactose
- Gelatin
- Purified water
- Glucose
- Glucose syrup
- Glutamate
- Glycerol
- Guar
H
- Hard grease
- Hexetidine
- Hyaluronic acid
- Hydroxyethyl cellulose
- Hydroxypropylcellulose
- Hypromellose
I
- Inulin
- Invertase
- Isomalt
- Isopropanol
- Isopropyl myristate
- Isopropyl palmitate
J
- Locust bean gum
K
- Potassium alginate
- Potassium benzoate
- Potassium chloride
- Potassium hydrogen carbonate
- Potassium hydroxide
- Potassium metabisulfite
- Potassium sorbate
- Kaolin
- Potato starch
- Carbon dioxide
- Hydrocarbons
L
- Lactitol
- Lactose
- Lanolin
- Lauric acid
- Lecithin
- Leucine
- Linolenic acid
M
- Macrogole
- Magnesium carbonate
- Magnesium oxide
- Magnesium silicate
- Magnesium stearate
- Corn oil
- Corn starch
- Maltitol
- Maltodextrin
- Maltose
- Malt extract
- Almond oil
- Mannitol
- Meglumine
- Menthol
- Methacrylic acid-ethyl acrylate copolymer dispersion
- Methyl 4-hydroxybenzoate
- Methyl cellulose
- Methylhydroxyethylcellulose
- Methylparaben
- Microcrystalline wax
- Lactic acid
- Lactose
- Medium chain triglycerides
- Monoethanolamine
- Monosodium phosphate
- Monosaccharides
- Myristic acid
N
- Sodium acetate
- Sodium alginate
- Sodium ascorbate
- Sodium benzoate
- Sodium chloride
- Sodium citrate
- Sodium dodecyl sulfate
- Sodium edetate
- Sodium hyaluronate
- Sodium hydrogen carbonate
- Sodium hydroxide
- Sodium lactate
- Sodium lauryl sulfate
- Sodium metabisulfite
- Sodium propionate
O
- Oleic acid
- Oleyl alcohol
- Olive oil
P
- Palmitic acid
- Palm oil
- Kerosenes
- Pectin
- Phenol
- Phenoxyethanol
- Phenylethyl alcohol
- Phosphoric acid
- Poloxamers
- Polyethylene glycols
- Polysaccharides
- Polysorbate 60
- Polysorbate 80
- Polysorbate
- Polyvinyl acetate phthalate
- Polyvinyl alcohol
- Povidone
- Propionic acid
- Propyl 4-hydroxybenzoate
- Propylene carbonate
- Propylene glycol
- Propyl gallate
- Propylparaben
R
- Raffinose
- Rapeseed oil
- Rice starch
- Castor oil
S
- Saccharin
- Sucrose
- Salmiak
- Hydrochloric acid
- Shellac
- Sulfur dioxide
- Sulfuric acid
- Sesame oil
- Silicon dioxide
- Simeticon
- Soybean oil
- Sunflower oil
- Sorbic acid
- Sorbitol
- Starch
- Stearic acid
- Stearyl alcohol
- Nitrogen
- Sucralose
- Sucrose
T
- Talk
- Thiomersal
- Thymol
- Ink for medicines
- Titanium dioxide
- Tragacanth
- Trehalose
- Triacetin
- Tributyl citrate
- Triethanolamine
- Trometamol
V
- Vanillin
- Vaseline
- Vitamin C
- Vitamin E
- Pregelatinized starch
W
- Water
- Water for injection
- Tartaric acid
- Wool wax
- Wool wax alcohols
X
- Xanthan gum
- Xylitol
- Xylose
- Zinc acetate
- Zinc stearate
- Citric acid
- Sugar alcohols
