3 - Liquid Dosage Forms (Manuf)

Name three kinds of liquid dosage forms.

Solutions, Syrups, and Juices

What is the primary characteristic of a pharmaceutical solution?

A homogeneous mixture where solute molecules are dispersed in a solvent.

How are pharmaceutical solutions classified?

By physical/chemical properties, method of preparation, use, physical state, number of ingredients, and particle size.

Why are most pharmaceutical solutions unsaturated?

Their solute concentration is below the solubility limit.

List four advantages of pharmaceutical solutions.

Homogeneous dosing, immediate absorption, flexible administration (oral/topical), easy dose adjustment.

What are the three methods of preparing solutions?

Simple solution, solution by chemical reaction, and solution by extraction.

Describe the steps to prepare a simple solution.

Dissolve solute in solvent → mix until dissolved → add solvent to final volume

What additional ingredient in simple solution method aids in the homogeneity of the mixture? Solubilizer/stabilizer

How does solution by chemical reaction differ from simple solution?

Solutes react chemically in the solvent

What is an example of a solution prepared by chemical reaction?

Magnesium Citrate Oral Solution, Aluminum subacetate solution, Sodium citrate and citric acid oral solution

What types of drugs are typically used in solution by extraction?

Drugs of vegetable or animal origin, extracted with water or water-based solvents.

Name four factors that hasten the dissolution process.

Application of heat, reducing solute particle size, using solubilizing agents, and rigorous agitation.

Why is reducing particle size important in solution preparation?

Increases surface area, speeding up dissolution.

Give examples of a simple solution.

Calcium Hydroxide Topical Solution, Strong Iodine solution, Sodium phosphate solution

Preparations utilizing solution by extraction may be classified as?

extracts

Which solution preparation method involves a reaction among ingredients?

Solution by chemical reaction

What are three synonyms for Magnesium Citrate Oral Solution?

Limonada purgante, Citrate of Magnesia, Liquor magnesii citratis.

What is the appearance and taste of Magnesium Citrate Oral Solution?

Colorless to slightly yellow, clear, effervescent liquid with sweet, acidulous taste and lemon flavor.

What is the standard adult dose of Magnesium Citrate Oral Solution?

200 mL.

What two components react to form the active ingredient in Magnesium Citrate Oral Solution?

Magnesium and anhydrous citric acid (forms Magnesium Citrate).

What is the function of syrup in this preparation?

Sweetening agent.

What is the purpose of talc in this solution?

Dispersing/clarifying agent.

Why is lemon oil included in the formulation?

Flavoring agent.

What role does potassium bicarbonate play?

Carbonating agent (creates effervescence).

What preparation method is used for Magnesium Citrate Oral Solution?

Solution by Chemical Reaction.

Why is sterilization important for this solution?

Enhances solution stability and reduces precipitation risk.

How should the solution be packaged and stored?

In 300 mL bottles, refrigerated, kept on its side to maintain airtight seal.

What is the therapeutic classification of Magnesium Citrate?

Saline laxative.

What are its two main clinical uses?

Treating constipation and bowel cleansing before colonoscopy.

What is its mechanism of action as a laxative?

Osmotic effect draws water into intestine → softens stool → stimulates peristalsis → produces watery stool.

How quickly does it typically work after administration?

30 minutes to 3 hours.

Which drug classes should not be taken within 2 hours of this solution?

Tetracyclines and quinolone antibiotics.

Why must these antibiotics be spaced apart from the solution?

To prevent decreased antibiotic absorption.

What can substitute for potassium bicarbonate in this formulation?

2.1 g sodium bicarbonate (preferably tablets).

How does citric acid monohydrate compare to anhydrous citric acid?

30 g monohydrate ≈ 27.4 g anhydrous.

What is the percentage strength of simple syrup?

85% w/v or 65% w/w.

What are three disadvantages of using sucrose?

Forms invert sugar during storage, may crystallize if supersaturated, promotes microbial growth.

Which patients should avoid sucrose-containing preparations?

Diabetic patients.

Name three alternative sweeteners to sucrose and their relative sweetness.

Aspartame, Dextrose, Glycerol, Mannitol, Saccharin sodium, Sorbitol

What key component must appear on the solution's label?

API (Active Pharmaceutical Ingredient).

How does aspartame's sweetness compare to sucrose?

160-200 times sweeter (artificial sweetener)

What advantage does dextrose offer over sucrose?

Reduces caramelization discoloration

What type of compound is glycerol?

Non-toxic sweet-tasting polyol

What two properties define mannitol?

Sugar alcohol and medication

Why might saccharin sodium be limited despite its sweetness?

300-550× sweeter but has bitter aftertaste

What distinguishes sorbitol's pharmacokinetics?

Not absorbed in gastrointestinal tract

Reactants forming magnesium citrate?

Magnesium carbonate + Citric acid

Products of magnesium citrate reaction?

Magnesium citrate + Water + CO₂

Carbonation reaction reactants?

Potassium bicarbonate + Citric acid

Carbonation reaction products?

Potassium citrate + Water + CO₂

What defines a pharmaceutical syrup?

Concentrated, viscous aqueous solutions of sugar/sugar substitute, with/without flavoring agents and medicinal substances.

What is the sucrose concentration in simple syrup?

85% w/v (purified water + sucrose only).

What is another use of syrups besides oral administration?

Sugar coatings for tablets to mask unpleasant tastes/aromas.

What are the four methods of syrup preparation?

Solution with heat, agitation without heat, adding sucrose to liquid medication, percolation (NF official method).

When is the heat method preferred?

For heat-stable components when rapid preparation is needed (80-85°C water).

What are examples of heat-prepared syrups?

Acacia Syrup, Cocoa Syrup, Syrup USP.

When is agitation without heat used?

For heat-sensitive/volatile components

What are examples of syrups prepared via agitation without heat?

Ferrous Sulfate Syrup, Ephedrine Sulfate Syrup, Citric Acid Syrup, Glycyrrhiza Syrup

How does the agitation method differ from heat?

Slower but yields more stable syrups

How are tinctures/fluidextracts incorporated into syrups?

Added directly to simple/flavored syrup if water-miscible, or rendered water-soluble.

What are examples of syrups prepared via addition of sucrose to a liquid medication?

Senna Syrup NF, Cherry Syrup

What is unique about the percolation method?

Purified water/medicinal solution passes through crystalline sucrose bed

Example of syrup prepared via percolation?

Tolu Balsam Syrup

How does 85% w/v sucrose act as a preservative?

Inhibits microbial growth (self-preserving concentration).

What are five chemical preservatives used in syrups?

Glycerin, benzoic acid, sodium benzoate, methylparaben, alcohol.

What physical method helps preserve syrups?

Low temperature storage.

How does heat vs. agitation affect syrup stability?

Agitation yields greater stability but takes longer than heat.

Why might percolation be preferred commercially?

Efficient for large-scale production of medicinal/confectionery syrups.

What is the active ingredient in Ferrous Sulfate Syrup?

Ferrous sulfate

What is the role of citric acid in Ferrous Sulfate Syrup?

Stabilizer that prevents oxidation of Fe²⁺ to Fe³⁺ (acts as antioxidant).

What percentage range must ferrous sulfate content be per 100mL?

NMT 3.75g NLT4.25g Ferrous sulfate, and NLT 0.75g NMT 0.85g elemental iron.

What are the synonyms of ferrous sulfate?

Green vitriol, Iron vitriol, Ferrosi Sulfas

What is the therapeutic classification of ferrous sulfate?

Hematinic (anti-anemic agent).

How does ferrous sulfate work as a hematinic?

Increases hemoglobin via erythropoiesis and improves erythrocyte hemoglobin content.

Why is ferrous sulfate particularly dangerous for children?

Can cause severe intoxication in overdose.

What are two drawbacks of ferrous sulfate oral solution?

Stains teeth and large doses can be toxic.

What are five agents that can prevent Fe²⁺ oxidation?

Glucose, lactose, citric acid, alcohol, citrate solutions.

What is the primary source material for pharmaceutical juices?

Fresh, ripe fruit.

What is the main pharmaceutical use of fruit juices?

As vehicles/flavoring agents in syrup preparations.

What are the six steps for preserving fruit juices?

1) Boil syrup 2) Sterilize bottles in hot water 3) Sterilize corks 4) Fill hot 5) Cork immediately 6) Dip in paraffin.

Why must bottles be filled with juice while still hot?

To maintain sterility before sealing.

Why is paraffin used in juice preservation?

Kills fermentation bacteria and creates hermetic seal.

What concentration of benzoic acid is used in pineapple juice preservation and pectin precipitant?

0.1% w/v.

What undesirable compound does benzoic acid precipitate from pineapple juice?

Pectin.

Why is standing time required after adding benzoic acid?

Allows complete pectin precipitation and enzymatic breakdown.

What simple test confirms pectin presence in juice?

Ethanol addition forms white gelatinous precipitate.

Why is pectin removal important?

Prevents precipitation during storage and maintains product texture.

What is the purpose of letting preserved pineapple juice stand?

Allows pectin precipitation and enzymatic breakdown.

How do you test for pectin in pineapple juice?

Add ethanol - white gelatinous precipitate indicates pectin.

What two preservatives are used in Cherry Juice USP XXI and Raspberry Juice USP XVIII?

Sulfurous acid or sodium metabisulfite.

How do artificial flavors compare to natural juices?

Artificial: more stable, easier to use but less complex flavor. Natural: authentic taste but less stable.

Which fruit juice has documented UTI benefits?

Cranberry juice.

What two urinary conditions does cranberry juice help manage?

UTIs and urolithiasis (kidney stones).

What is raspberry juice used for?

as a flavored vehicle