Excipients for Liquid

For liquid Dosage form : 

 

Preservative : which prevent microbial growth?

For example – Benzyl alcohol / Phenol / Benzyl conium chloride / Methyl paraben, Propyl paraben / Butyl paraben / Boric acid / Sodium salicylate / Thimersal

Emulsifying agent / Surface active agents (reduce surface tension) : 

To reduce internal phase into small globules / Stabilizer of the droplet form of the internal phase of an emulsion. Emulsifiers are also used as a wetting agents & Surfactant.

*Surface tension – Interfacial tension at an air liquid interface. Surface tension causes fluids to assume spherical shape.

For example – Egg yolk, Agar, honey, gelatin, Na Alginate,Polysorbate (80, 60, 20) / Potassium oleate / Sodium dodecyl (lauryl) suphate / Povidone / Propylene glycol / Theophylene / Propylene glycol / Ethyl alcohol / Glycerin

Anti-oxidant : It helps to prevent oxidation

For example –

Anti-oxidant (reducing agents) – Sodium bi sulphate / Butylated anisole / Thiourea /

Anti-oxidant (blocking agents) – Tocopherol / Ascorbic acid esters

Synergist –Ascorbic acid (vitamin – C) / Phosphoric acid / Tartaric acid / Citric acid

Suspending agents: 
Agents used in pharmaceutical suspensions to impart viscosity

For example – Gelatin / Methyl cellulose / Sobitol solution / Polyethylene glycol 4000