[PHA 619 LAB] Prep 26 and 29 - Non-aqueous Liquids: Glycerites and Gels

It is a preparation used to prepare aqueous and alcoholic dilutions of substances readily soluble in water or alcohol. Most are viscous while some are jelly-like.

Glycerites

(True/False) Some glycerites are viscous, but most are jelly-like.

False

- MOST glycerites are viscous.

Composition of glycerite

Solution of medicinal substances in not less than 50% by weight of glycerin

Example of solution that uses glycerite as solvent

Antipyrine and Benzocaine Otic Solution

What is major component and solvent of glycerites?

Glycerin

Uses of glycerites

- Protectant

- Emollient

- Pill excipient

- Substitute for fatty ointment

Glycerites are ___________ since they absorb water and moisture from the atmosphere.

Hygroscopic

Glycerites are stored in?

Tightly-closed container

(True/False) Glycerin is an oxidizing agent that, when mixed with another strong oxidizing agent, may cause an explosion.

False

- Glycerin is a REDUCING agent.

Why is glycerin not triturated or combined with a strong oxidizing agent?

Explosion may occur

Examples of strong oxidizing agents that glycerin must not be combined with

- KMnO4

- Chromium trioxide

- KClO3

Upon contamination with iron, glycerin produces coloration with what compounds?

- Phenol

- Salicylates

- Tannin

These reagents convert glycerin into an explosive nitrogyclerin.

Strong HNO3 / H2SO4

Composition of glycerin

Has three hydroxyl groups, making it soluble in water and hygroscopic

Glycerin is also called as?

Glycerol

Category of starch glycerites

Gel

Synonyms of starch glycerites

- Glyceratum amyli

- Starch glycerin

- Glycamyl

Formulation of starch glycerite

- Starch (3 g)

- Benzoic acid (0.06 g)

- Purified water (6 mL)

- Glycerin (16.8 mL)

Desired description of starch glycerite

Translucent, jelly-like mass

At what temperature is the mixture of starch glycerite heated?

140 - 144 C

Uses of starch glycerite

- Topical vehicle

- Protectant

Label used for starch glycerite

Red Label

Container used for starch glycerite

30 mL suppository bottle

- Alternative: Wide-mouth flint bottle

Method of preparation for starch glycerite

Trituration

Starch glycerite must be stored in?

Tightly-closed container

It is a suspension, in a water medium of insoluble drugs in hydrated form wherein the particle size approaches or

attains colloidal dimension.

Gels

What happens to gels if undistributed for some time?

Become semisolid or gelatinous with some small amount of water separating on standing

What happens to gels if distributed/shaken?

They liquefy.

Property of gels wherein they displace high viscosity in the semisolid state on standing and low viscous liquid upon agitation.

Thixotropy

Desired particle size in gels to achieve a large surface and thus maximum adsorption capacity.

Very fine

Gels may contain peppermint oil, glycerin, sorbitol, sucrose, saccharin, or other suitable flavor and preservatives in a total amount not exceeding?

0.5%

Category of aluminum hydroxide gel

Medicated gel

Synonyms of aluminum hydroxide gel

- Colloidal Aluminum hydroxide

- Amphojel

- Alternagel

It is a white, viscous preparation from which a small amount of water may be separated on standing. It is translucent in a thin layer. It affects both red and blue litmus paper slightly but is not reddened by phenolphthalein.

Aluminum Hydroxide Gel

Aluminum hydroxide gel may be reddened by?

Phenolphthalein

Uses of aluminum hydroxide gel

- Antacid (w/o systemic alkalosis)

- Skin protectant and mild astringent

Possible side effect of aluminum hydroxide gel

Constipation

- due to aluminum

Formulation of aluminum hydroxide gel

- Ammonium alum (12 g)

- Sodium carbonate (15 g)

- Peppermint oil (0.003 g)

- Sodium benzoate (0.03 g)

- Purified water, qs ad (30 mL)

How many percent of peppermint oil and sodium benzoate each must be in the preparation of aluminum hydroxide gel?

0.01%

Label used for aluminum hydroxide gel

White label with shake well

Container used for aluminum hydroxide gel

60 mL wide-mouth amber bottle

Method of preparation used for aluminum hydroxide gel

Chemical Reaction

(True/False) Aluminum hydroxide gel produces no systemic alkalosis.

True

(True/False) Aluminum hydroxide gel is used for constipation.

False

- It only CAUSE constipation (side effect).

It decreases the absorption of certain

drugs, like tetracycline. It also interferes with the deframing action of simethicone.

Aluminum

Aluminum can form __________ with other metals and can react with some antibiotics and dairy products because they contain calcium.

Chelate

Preservative used in aluminum hydroxide gel

Sodium benzoate