Module 2: Excipients

pH modifiers

decreases/increases pH in preparation or protects compounds from rapid change in pH

absorbent

holds other molecules onto its surface by physical and chemical (chemisorption) means

chelating agent

substance that forms stable water-soluble complexes with metals

-used in some liquid pharmaceuticals as stabilizers to complex heavy metals that might promote instability

clarifying agent

filtering aid used for its absorbent qualities

antifungal preservative

prevents growth of fungi in liquid and semi solid preparations. Sometimes combined with antimicrobial preservatives like parabens to enhance their effectiveness

antimicrobial preservatives

prevents growth of microorganisms in liquid and semisolid preparations

aerosol propellant

develops pressure with an aerosol container, which expels the ingredient when the value is open

Colorant

used to impart color to liquid and solid preparations

Flavorant

gives a pleasant flavor to a preparation. Synthetic ones may also be used in addition to the natural ones listed (anise oil, cinnamon oil, cocoa, methanol, Vanillin)

Sweetening agent

imparts a pleasant flavor and sweetness to a preparation (ie. aspartame, sucrose)

Solvents

in preparation of a solution, aqueous/oleaginous solvent maybe used to dissolve another substance. Water and hydroalcoholic mixtures, water, and glycerin, may be used as co-solvent when needed.

Hydrophilic solvent

liquid with highly miscible with water, used to dissolve solutes

Hydrophobic solvents

liquid without low/no miscibility with water , used to dissolves solutes

Surfactant

substances that absorb to surfaces/interfaces to reduce surface or interfacial tension. May be used as wetting agents, detergents, or emulsifying agents

emulsifying agent

promotes and maintains dispersion of the finely subdivided particles of liquid in vehicles where it is immiscible. A liquid emulsion or semisolid emulsion may be end product

suspending agent

viscosity-increasing agent used to reduce sedimentation rate of particles in vehicle in which they are not soluble

tonicity agent

makes a solution similar in osmotic characteristics to physiologic fluid such as irrigation, ophthalmic, and parental fluids

vehicle

a base used in a variety of liquids for oral and parental administration. Oral liquids are aqueous (syrups) or hydroalcoholic

Viscosity-increasing agent

renders preparation more resistant to flow. In suspension, sedimentation is deterred and they can be also called suspending agents, contact time is enhanced in ophthalmic solutions and topical creams are thickened

water-miscible co-solvent

increases the solubility of poorly water-soluble substances or enhances the chemical stability of a drug

wetting agent

reduces surface tension of water, allowing it to spread more easily

antifoaming agent

breaks up and inhibits the formation of foams

foam adjuvant

improves stability and reduces the specific gravity of foam. May increase the foaming capacity of surfactants

Foaming agent

amphiphilic substance that facilitates the formation of foam

Gelling agent

increases the viscosity of a substance; can act as a stabilizer

Humectant

Prevents drying of preparations, particularly ointments and creams

Levigating agent

the liquid that is used as an intervening agent to reduce that particle size of a powder by grinding, usually in a mortar

Ointment base

semisolid vehicle for medicated ointments

Stiffening agent

increases thickness or hardness of preparation, usually an ointment

water-repelling agent

hydrophobic material used as a non-sticky lubricant in lotions in creams or as an enhancer and stabilizer foams

suppository base

vehicle for suppositories (cocoa butter, polyethylene glycol)

encapsulating agent, coating

forms thin shells in which drug is enclosed to ease administration

enteric coating

polymer barrier on tablets meant to prevent the medication from breaking down in the stomach, while allowing breakdown in the small intestine

film coating

polymer coating applied to tablets meant to protect the doage form or modify its release

sugar-coating

sweetened outer layer on oral solid dosage forms

Plasticizer

component of film-coating solutions to make the film more pliable, enhance the spread of coat over tablets, beads, and granules

Tablet anti-adherent

prevents tablet ingredients from sticking to punches and dies during production

Tablet binder

substances that cause adhesion of powder particles in tablet granulations

Tablet and capsule diluent

inert filler that creates desired bulk, flow properties, and compression characteristics of tablets and capsules

tablet direct compression excipient

for use in direct compression tablet formulations

Dose Reproducibility, Spatial and Temporal Drug Delivery, Improve Drug Absorption, Improve Product Stability, Aid in Identification, Enhance Patient Compliance

What is the purpose/importance of excipients?

Dose reproducibility

What purpose connects to formulation of potent drugs?

Spacial and Temporal Drug Delivery

What purpose focuses on target organ transportation (intestine) and extended release products?

Improve Drug Absorption

What purpose is connected to solubility and disintegration time?

Improve Product Stability

What purpose is connected to antioxidants?

Aid in Identification

What purpose focuses on color and symbol of drugs?

Enhance Patient Compliance

What purpose focuses on making patients more likely to take meds? This can include making drug taste better

allergic reaction, intolerance, drug-excipient interactions or excipient-excipient, excipients slowing down drug dissolution

Potential issues with excipient use

tablet disintegrant

promotes disruption of the mass in a solid form into smaller particles that are more easily dispersed or dissolved

tablet glidant

improves flow of properties of the powder mixture in tablet and capsule formations

tablet lubricant

reduces friction of tablet formulations during tablet compression, and prevents their sticking to punches and dies, facilitating tablet ejection

tablet or capsule opaquant

renders a coating opaque when used alone or with a a colorant

tablet polishing agent

gives an attractive sheen to coated tablets

antioxidant

prevents deterioration or preparations by oxidation