20 Most Common Pharmaceutical Additives with Examples

A pharmaceutical additive or an excipient is a substance that mixed with an active pharmaceutical ingredient for a specific purpose.

I will go through the most common types with examples:

 1.  Antioxidant :  

It is an agent that prevent the oxidation process to the pharmaceutical preparation. Thus, avoid its deterioration.

Examples:

Antioxidants as a pharmaceutical additives have two types:

Type	Water Soluble	Lipid Soluble
Examples	Ascorbic Acid – known as Vitamin C. Hypophosphorous acid.	Tocoferal – known as Vitamin E1. Butylated hydroxyanisole (BHA). Butyllated hydroxytoluene (BHT).

 2. Humectants:  

Simply, related to humidity, so the basic function is to keep the preparation wet and avoid dryness like in ointment and creams.

Examples:

• Glycerin.
• Propylene glycol.
• Sorbitol.

 3. Stiffening Agents:  

Are used to increase the thickness of the pharmaceutical preparations as in an ointments.

Examples : White Wax, Yellow Wax and Paraffin.

 4. Suspending Agents:  

Are used to increase the viscosity of the vehicle to reduce the rate of sedimentation. Usually the drug is not soluble in the vehicle and a suspending agent is required. Drugs of that type often require the statement “Shake before Use”.

Examples : Agar, Gum tragacanth and Bentonite.

 5. Flavoring Agents:  

Are used to enhance the pharmaceutical preparation taste and odour.

Examples : usually volatile oils like Anise oil, cinnamon oil, Cocoa, Menthol and strawberry flavors.

 6. Coloring Agents (Colorant):  

Are used to add a color to liquid preparations.

Examples : Caramel.

 7. Sequestering Agents (Chelating Agents):  

Agents that are used to form stable complex with metals, they are used as stabilizers in cases of instability caused by metals especially in liquid pharmaceutical preparations.

Examples : EDTA ( Ethyele Diamine tetra acetic acid).

 8. Anti-Adherent agents:  

Usually used in tablet preparations to avoid the sticking of tablet ingredients.

Examples : Talc & Silicon Dioxide.

 9. Polishing agents:  

Usually used in tablet preparations to be more attractive.

Examples : White Wax & Carnauba Wax.

 10. Emulsifying agents (emulgent):  

They are agents that are soluble in both Fat & Water. have hydrophilic and lipophilic characters and used to enhance the stability of the emulsion avoiding the separation between the two phases. They are also known as surfactant or surface active agents.

Examples:

Anionic	Non Ionic	Cationic
Sodium lauryl sulfate Glycerl monoestearate	Tweens and spans	Benzalkonium chloride

 11. Solvent:  

An agent that used to dissolve a pharmaceutical substance which might be hydrophilic or lipophilic substance.

Examples:

• Water of Injection.
• Sterile Water for Injection.
• Olive oil.
• Corn Oil.
• Purified Water.
• Glycerin.
• Mineral Oil.

 12. Coating Agent:  

Mainly used in tablet manufacturing, the main purpose for adding a coating agent is to protect the tablet and its drug components from external factors like Oxygen, humidity or to mask unpleasant odor or taste.

Types of Tablet Coating:

• Sugar coating: The Tablet to be break up in the stomach.
• Film coating:   Thin film around the formed tablet and usually dissolves in the stomach.
• Enteric coating:   The Tablet to be break up in the intestine.

Examples:

Sugar Coating	Film Coating	Enteric Coating
Liquid glucose. Sucrose.	Methyl Cellulose. Ethyl Cellulose.	Shellac. Methacrylic acid

 13. Adsorbent:  

An agent that used to adsorb and bind with other agent onto its surface either physically or chemically.

Examples:

• Activated Charcoal. ( The most popular adsorbent)
• Powdered cellulose.

 14. Preservatives:  

Agents used to protect the pharmaceutical preparations usually liquids and semi-solids from deterioration by micro-organisms or fungi.

Examples:

Antimicrobial	Anti-fungals
Benzalkonium Chloride. Benzyl Alcohol. Phenol. Thimerosal.	Benzoic Acid. Butyl Paraben. Sodium Benzoate. Paraben-ees.

 15. Buffering Agents:  

Agents that used to prevent the change of PH of the pharmaceutical preparations. Buffers are made with Acids or bases and their salts.

Examples:

• Potassium metaphosphate.
• Potassium phosphate Monobasic.
• Sodium acetate.
• Sodium citrate anhydrous and dehydrate.

 16. Disintegrant:  

Agents to make sure when the tablet in contact with the dissolving medium, they broke up into smaller particles. Thus, facilitating their dissolution. In simple words, agents that are responsible for tablet rupture.

Examples:

Starch, cellulose, crosses linked polyvinyl pyrrolidone, sodium starch glycolate, sodium carboxymethyl cellulose.

 17. Binders:  

Binders are responsible for the adhesion of the drug with the inactive ingredients in the tablet manufacturing.

There are two types of binders: