Pharmacology: Rectal Suppositories Quiz

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Questions and Answers

Which of the following is NOT a physiological factor affecting drug absorption from rectal suppositories?

  • Colonic contents
  • Circulation route
  • Particle size of the drug (correct)
  • pH and lack of buffering capacity of rectal fluids

What is the primary mechanism by which glycerin suppositories promote laxation?

  • Lubrication of the rectal lining
  • Softening of the fecal matter
  • Local irritation of the mucous membranes (correct)
  • Stimulation of intestinal motility

Why are rectal suppositories sometimes preferred over oral administration for systemic effects?

  • Rectal administration is more convenient for patients who are unable to swallow medication.
  • Rectal administration bypasses the first-pass metabolism in the liver. (correct)
  • Rectal administration ensures faster absorption of the drug.
  • Rectal administration eliminates the risk of drug interactions.

Which of the following is NOT a common component found in anti-hemorrhoidal suppositories?

<p>Antibiotics (D)</p> Signup and view all the answers

What is the primary advantage of using a suppository base that melts rapidly at body temperature?

<p>It ensures that the drug is readily absorbed by the rectal mucosa. (D)</p> Signup and view all the answers

Which of the following statements correctly describes the role of lymphatic circulation in rectal drug absorption?

<p>Lymphatic circulation helps in the absorption of rectally administered drugs, alongside the lower hemorrhoidal veins. (B)</p> Signup and view all the answers

Why is it important to consider the physicochemical properties of the drug when formulating a rectal suppository?

<p>To ensure the drug is released at the correct rate and available for absorption. (C)</p> Signup and view all the answers

Which of the following factors would MOST likely hinder the absorption of a rectally administered drug?

<p>The presence of a large amount of fecal matter in the rectum. (C)</p> Signup and view all the answers

Which of the following drugs is commonly administered rectally for systemic effects?

<p>Prochlorperazine (D)</p> Signup and view all the answers

What is the significance of the fact that rectal fluids have no effective buffer capacity?

<p>This means that the drug's chemical form will generally remain unchanged in the rectal environment. (B)</p> Signup and view all the answers

Why might the dose of a drug administered rectally differ from the oral dose of the same drug?

<p>Because of the different mechanisms of drug absorption in the rectum and the stomach. (B)</p> Signup and view all the answers

Which of the following is NOT a physicochemical factor that can affect drug absorption from rectal suppositories?

<p>The pH of the rectal fluids (C)</p> Signup and view all the answers

What is the primary reason why the vaginal route is not frequently used for systemic drug administration?

<p>Vaginal absorption is significantly slower than rectal absorption. (A)</p> Signup and view all the answers

Which of the following best describes the role of cocoa butter as a suppository base?

<p>Cocoa butter melts quickly at body temperature but may not readily release fat-soluble drugs due to its immiscibility with fluids. (D)</p> Signup and view all the answers

Which of the following statements accurately describes the advantages of rectal drug administration over oral administration for systemic effects?

<p>Rectal administration bypasses the first-pass metabolism in the liver, allowing for higher bioavailability of certain drugs. (D)</p> Signup and view all the answers

Why is a lower lipid-water partition coefficient advantageous for a drug when using a fatty suppository base?

<p>A lipophilic drug with a lower partition coefficient will be more readily absorbed by the surrounding aqueous fluids. (B)</p> Signup and view all the answers

Which type of suppository base would be most suitable for a drug with low solubility in both water and fat?

<p>Intermediate base (C)</p> Signup and view all the answers

Which of the following is NOT a desirable property of an ideal suppository base?

<p>Irritant to mucous membranes (A)</p> Signup and view all the answers

What is the primary reason for the rapid release of fat-soluble drugs from water-soluble suppository bases?

<p>Water-soluble bases dissolve quickly in body fluids, allowing the drug to easily enter the bloodstream. (D)</p> Signup and view all the answers

What is the significance of the particle size of an undissolved drug in a suppository?

<p>Smaller particles have a larger surface area, enhancing the rate of dissolution and absorption. (B)</p> Signup and view all the answers

What is the primary function of a suppository base?

<p>To act as a carrier for the drug and facilitate its release for absorption. (A)</p> Signup and view all the answers

Which of the following is a potential disadvantage of using a fatty suppository base like cocoa butter?

<p>It can be susceptible to polymorphism, potentially affecting drug release. (C)</p> Signup and view all the answers

Why is it crucial to consider the potential interaction between the drug and the suppository base during formulation?

<p>To ensure that the base does not inactivate or reduce the bioavailability of the drug. (A)</p> Signup and view all the answers

Which of the following best describes the ideal melting point of a suppository base?

<p>A melting point slightly below body temperature to facilitate steady drug release. (C)</p> Signup and view all the answers

What is the main reason why cocoa butter is considered a superior base for treating anorectal disorders?

<p>Its emollient property provides soothing and spreading action on irritated tissues. (D)</p> Signup and view all the answers

What is the significance of a suppository base contracting on cooling?

<p>It allows for easier removal of the suppository from the mold. (B)</p> Signup and view all the answers

Which of the following represents the best practice for melting cocoa butter for suppository formulation?

<p>Melting at the minimum required temperature and allowing it to cool slowly. (A)</p> Signup and view all the answers

Which of the following factors does NOT directly affect the rate of drug absorption from a suppository?

<p>The patient's metabolism. (C)</p> Signup and view all the answers

What is the primary advantage of using glycerinated gelatin or polyethylene glycol as suppository bases?

<p>They are compatible with both fat-soluble and water-soluble drugs. (C)</p> Signup and view all the answers

Based on the text, what would likely happen if a suppository base irritates the mucous membranes of the rectum?

<p>It could trigger a bowel movement, potentially reducing drug absorption. (C)</p> Signup and view all the answers

Which type of crystalline form of cocoa butter is more stable and has a higher melting point?

<p>Beta crystals (A)</p> Signup and view all the answers

What is the primary reason for adding a lubricant agent to a Theobroma oil based suppository?

<p>To prevent the suppository from sticking to the mold during the cooling process. (A)</p> Signup and view all the answers

Which of the following bases is characterized by a slowly dissolving property in bodily fluids?

<p>Glycerinated gelatin (C)</p> Signup and view all the answers

Which of the following suppository bases is most commonly used in the preparation of vaginal suppositories?

<p>Glycerinated gelatin (C)</p> Signup and view all the answers

Which of the following is NOT a disadvantage of glycerinated gelatin-based suppositories?

<p>They have a higher melting point than cocoa butter. (D)</p> Signup and view all the answers

What is the primary function of a surface-active agent in suppository bases?

<p>To promote the formation of water-in-oil emulsions. (A)</p> Signup and view all the answers

Which of the following statements accurately describes the melting properties of Polyethylene Glycol (PEG) suppositories?

<p>They do not melt at body temperature but dissolve slowly in bodily fluids. (A)</p> Signup and view all the answers

What specific issue with cocoa butter makes it unsuitable for warm climates?

<p>Its low melting point may cause it to melt at room temperature. (B)</p> Signup and view all the answers

Which of the following ingredients is commonly included in commercial suppository bases to enhance water absorption?

<p>Glyceryl monostearate (E)</p> Signup and view all the answers

Which of the following suppository bases is most likely to be preferred in a situation where the medication needs to be released quickly?

<p>Cocoa butter (A)</p> Signup and view all the answers

What is the primary reason why PEG suppositories should be dipped in water before insertion?

<p>To minimize the risk of irritation to the mucous membrane, preventing moisture loss from the tissue. (A)</p> Signup and view all the answers

Which of the following statements about the melting point of Theobroma oil is ACCURATE?

<p>The melting point of Theobroma oil can vary depending on the crystal form it forms during solidification. (A)</p> Signup and view all the answers

Which of these suppository bases is NOT a triglyceride?

<p>Glycerinated gelatin (D)</p> Signup and view all the answers

Which of the following methods of suppository preparation is most commonly used in both small-scale and industrial settings?

<p>Molding from a melt (C)</p> Signup and view all the answers

What is the average polymer length of Polyoxyl 40 Stearate, a surface-active agent used in suppository bases?

<p>40 (B)</p> Signup and view all the answers

Which of the following suppository bases is specifically designed to accommodate aqueous solutions?

<p>Fattibase (C)</p> Signup and view all the answers

Which of these suppository bases can be used to prepare suppositories with a higher melting point than body temperature?

<p>Polyethylene Glycol (E)</p> Signup and view all the answers

Calculate the quantity of glycerin gelatin base required to prepare six glycero gelatin supps (4 g mold) each containing 100 mg aminophylline: (Displacement Value = 1.3).

<p>28.25 g (B)</p> Signup and view all the answers

What is the primary reason for buffering vaginal suppositories to an acidic pH of approximately 4.5?

<p>To discourage the growth of pathogenic organisms (F)</p> Signup and view all the answers

Which of the following is not a common component of vaginal tablets (inserts)?

<p>Theobroma oil (B)</p> Signup and view all the answers

What is the primary reason for using a plastic inserter with vaginal tablets?

<p>To ensure accurate placement of the tablet within the vagina (C)</p> Signup and view all the answers

Why are suppositories containing light-sensitive drugs wrapped in an opaque material?

<p>To prevent the drug from degrading due to exposure to light (B)</p> Signup and view all the answers

What is the primary reason for storing cocoa butter suppositories below 30°C?

<p>To prevent the suppository from becoming too soft and melting (E)</p> Signup and view all the answers

What is the primary difference between vaginal suppositories and vaginal tablets (inserts) in terms of their composition?

<p>Vaginal tablets contain disintegrating agents, while vaginal suppositories do not. (E)</p> Signup and view all the answers

Which type of suppository base requires storage at controlled room temperature (20°C to 25°C)?

<p>Glycerinated gelatin (B)</p> Signup and view all the answers

How is the displacement value of a drug determined?

<p>By comparing the weight of the drug to the weight of the base it replaces. (A)</p> Signup and view all the answers

What adverse effect can occur if suppositories are stored in high humidity?

<p>The suppositories may become spongy (D)</p> Signup and view all the answers

Which of the following statements about suppository shapes and sizes is NOT accurate?

<p>All suppositories are designed to be easily inserted into the intended orifice without causing undue distension. (C)</p> Signup and view all the answers

Which of the following suppository types is typically used for local anesthetic purposes?

<p>Urethral suppository (C)</p> Signup and view all the answers

Which of the following is NOT a common shape for vaginal suppositories?

<p>Cylindrical (D)</p> Signup and view all the answers

If a suppository base is primarily composed of cocoa butter, what is the approximate weight of a typical adult rectal suppository?

<p>2 g (D)</p> Signup and view all the answers

What is the primary purpose of the suppository base in terms of its interaction with the body?

<p>To dissolve, melt, or soften upon insertion, releasing the medication (D)</p> Signup and view all the answers

Which of the following statements accurately describes the fate of a suppository once inserted?

<p>The suppository base melts, softens, or dissolves, releasing the medication into the surrounding tissues. (D)</p> Signup and view all the answers

What is the intended purpose of urethral suppositories for men, aside from their antibacterial properties?

<p>To prepare the urethra for an upcoming examination (D)</p> Signup and view all the answers

Which of the following statements accurately reflects the purpose of suppositories?

<p>To deliver medication with both local and systemic effects based on the drug's properties. (A)</p> Signup and view all the answers

What is the primary reason for preparing one or two extra suppositories when calculating the amount of base?

<p>To compensate for the loss of material during preparation. (D)</p> Signup and view all the answers

What is the main consideration when determining the amount of base required for a medicated suppository?

<p>The volume of the mold. (C)</p> Signup and view all the answers

Which of the following is NOT a suitable base for suppository preparation by molding?

<p>Sodium chloride (B)</p> Signup and view all the answers

What is the primary reason for using a warm mortar when preparing suppositories by compression?

<p>To facilitate the softening and mixing of the base. (B)</p> Signup and view all the answers

Which of the following methods of suppository preparation is considered the oldest and simplest?

<p>Hand rolling and shaping (C)</p> Signup and view all the answers

What is the volume of cocoa butter required if a 12 mL suppository mold is used and the medicaments have a collective volume of 2.8 mL?

<p>9.2 mL (D)</p> Signup and view all the answers

What is the significance of the density factor in suppository preparation?

<p>It determines the weight of the base required. (D)</p> Signup and view all the answers

What is the displacement value of a drug that displaces an equivalent volume of the base?

<p>1 (C)</p> Signup and view all the answers

If the density of a drug is greater than the density of the base, how will the displacement value affect the amount of base required?

<p>The drug will displace a lesser volume of base, requiring less base. (D)</p> Signup and view all the answers

Which of the following is NOT a factor influencing the displacement value of a drug?

<p>Volume of the mold (C)</p> Signup and view all the answers

What is the displacement value of hydrocortisone?

<p>1.5 (A)</p> Signup and view all the answers

What is the total weight of codeine phosphate required to prepare 10 suppositories, each containing 60 mg of codeine phosphate?

<p>0.6 g (C)</p> Signup and view all the answers

If a suppository mold has a size of 1 g, how much base is displaced by 0.6 g of codeine phosphate with a displacement value of 1.1?

<p>0.55 g (B)</p> Signup and view all the answers

What is the total weight of base required to prepare 10 unmedicated suppositories using a 2 g mold?

<p>20 g (D)</p> Signup and view all the answers

What is the total quantity of zinc oxide required to prepare 10 suppositories, each containing 400 mg of zinc oxide?

<p>4 g (D)</p> Signup and view all the answers

Why is it important to consider the volume of medicaments when preparing suppositories?

<p>To avoid exceeding the maximum allowable volume in the mold. (B)</p> Signup and view all the answers

Flashcards

Suppositories

Solid dosage forms for insertion into body orifices that melt, soften, or dissolve to deliver medications.

Rectal Suppositories

Cylindrical suppositories usually 32 mm long, used rectally, typically weighing about 2 g.

Vaginal Suppositories

Globular or cone-shaped suppositories used vaginally, often weighing about 5 g when cocoa butter is used.

Urethral Suppositories

Slender, pencil-shaped suppositories used for insertion into the urethra, differing in size for males and females.

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Suppository Base

The material that forms the body of the suppository, melts, softens, or dissolves to release medication.

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Adult vs. Pediatric Suppositories

Adult rectal suppositories weigh about 2 g; those for children weigh about half that and are smaller.

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Delivery Method

Suppositories can exert local effects (at the insertion site) or systemic effects (through absorption into circulation).

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Fate of the Suppository

After insertion, the base dissolves to distribute the medicaments to surrounding tissues.

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Retention Medicaments

Medicaments designed for local effects or systemic absorption.

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Slow-Release Suppositories

Suppositories that release medication over extended periods.

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Morphine Sulfate

A pain reliever available in slow-release suppository form.

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Glycerin Suppositories

Used to relieve constipation by irritating mucous membranes.

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Anti-Hemorrhoidal Suppositories

Suppositories that relieve pain and inflammation due to hemorrhoids.

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Local Vaginal Suppositories

Used for contraception, antiseptics, and antifungal treatments.

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Systemic Effects of Suppositories

Drugs absorbed rectally can have systemic effects.

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Advantages of Rectal Route

Bypasses stomach's destructive environment.

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Factors Affecting Absorption

Includes drug physicochemical nature and suppository vehicle.

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Physiological Factors

Body conditions affecting rectal absorption, such as contents and pH.

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Colonic Content

Fecal matter affects drug absorption; emptier is better.

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Bypassing Portal Circulation

Allows rectally administered drugs to avoid liver degradation.

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pH of Rectal Fluids

Neutral pH helps maintain drug integrity during absorption.

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Physicochemical Drug Factors

Includes solubility, particle size, and pKa impacting absorption.

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Suppository Base Properties

Attributes of the base that affect drug release like melting and consistency.

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Cocoa Butter Melting

Cocoa butter must be melted slowly to maintain stable beta crystals.

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Theobroma Oil Polymorphism

Theobroma oil can form stable and unstable crystalline structures at different temperatures.

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Stable β-Polymorph

Stable crystal form of cocoa butter formed by melting under 36°C.

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Unstable γ-Form

Unstable crystal form formed if cocoa butter melts quickly at high temperature.

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Cocoa Butter Adherence

Cocoa butter can adhere to molds, solved by using lubricants.

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Low Melting Point Issue

Cocoa butter has a low melting point which can be improved by adding white beeswax.

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Water Absorption Problem

Cocoa butter has low water absorbance; surface-active agents can improve this.

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Glycerinated Gelatin

Water-soluble base made of gelatin (20%) and glycerin (70%) for suppositories.

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PEG Properties

Polyethylene glycols (PEG) dissolve in body fluids, do not melt at body temperature.

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PEG Chain Lengths

PEG is available in various molecular weights for different properties.

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Preparation Methods for Suppositories

Suppositories can be made by molding, compression, or hand rolling.

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Moisture Protection for Suppositories

Glycerinated gelatin must be protected from moisture to avoid shape loss.

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Irritation from Glycerinated Gelatin

Glycerinated gelatin can irritate tissues due to its dehydrating effect.

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Miscellaneous Suppository Bases

Bases are mixtures of fatty and water-soluble materials, allowing for diverse formulations.

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Molding Steps

The process of preparing suppositories through melting, mixing, pouring, cooling, and removing them from molds.

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Materials for Molding

Common bases used for molding suppositories include cocoa butter, glycerinated gelatin, and polyethylene glycol.

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Suppository Molds

Molds can be made from stainless steel, aluminum, brass, or plastic and are designed to create the shape of suppositories.

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Cleaning Molds

Careful cleaning of molds before and after use is crucial to maintain the smoothness of suppositories.

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Preparation by Compression

A method where medicaments are forced into molds, requiring thorough mixing of ingredients to create a paste.

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Hand Rolling Method

The oldest method of suppository preparation that involves manually shaping the suppositories.

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Calculating Base Amount

Pharmacists calculate slightly more base than needed to account for losses in preparation.

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Volume Consideration

The volume of active medicaments must be subtracted from the total mold volume to determine the base volume.

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Density Calculations

Density factors help convert the volume of base to weight for suppository preparation.

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Dosage Replacement Factor

A method to calculate how much base is needed based on the volume the medication displaces.

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Displacement Value (D.V)

Defines the amount of drug displacing the base, helping to calculate total base needed.

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Codeine Phosphate Example

Calculation example for preparing suppositories with codeine phosphate and displacement value considered.

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Zinc Oxide Calculation

Example of how to calculate the weight of base needed for ten zinc oxide suppositories using displacement value.

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Volume Methods

Methods for determining the base quantity needed based on the occupied volume of the drug in the mold.

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Lipid-Water Partition Coefficient

A measure of drug solubility in lipid versus water, affecting drug release.

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Lipophilic Drug

A drug that prefers fat environments, impacting its absorption in fatty bases.

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Hydrophilic Drug

A drug that prefers water environments, influencing its release in aqueous bases.

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Choice of Base

Depends on drug solubility; fatty for lipophilic, aqueous for hydrophilic.

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Amount of Drug

Higher concentration in the base increases absorption until a saturation point.

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Particle Size

Smaller drug particles have more surface area, enhancing dissolution and absorption.

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Ideal Suppository Base Properties

Non-toxic, compatible, stable, and melts or dissolves at body temp.

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Fatty Bases

Solid at room temp, melts quickly; often used for fat-soluble drugs.

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Water-Soluble Bases

Use polyethylene glycol or glycerinated gelatin; good for water-soluble drugs.

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Cocoa Butter

Fatty base that melts at body temperature, commonly used in suppositories.

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Polymorphism of Cocoa Butter

Cocoa butter can exist in multiple crystalline forms affecting melting point.

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Metastable Crystalline Form

An unstable form of cocoa butter that melts at lower temperatures.

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Rate of Absorption

Influenced by drug concentration and solubility in the base.

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Suppository Interaction

Chemical/physical interactions between the drug and the base may affect stability.

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Wetting Properties

The ability of a base to spread on a surface, influencing drug release.

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Weight of Base Required

Total mass of base needed to prepare medicated suppositories after accounting for displacement by the drug.

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Displacement Value

The weight of a base displaced by a drug; used to adjust amount of base required.

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Glycero-Gelatin Base

A semi-solid base used for suppositories, denser than cocoa butter and often used in vaginal formulations.

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Vaginal Suppository Composition

Commonly made of polyethylene glycols with added surfactants and preservatives for stability.

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Vaginal Tablets vs. Suppositories

Vaginal tablets are easier to manufacture, more stable, and less messy than suppositories.

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Storage Conditions for Suppositories

Maintaining suppositories in a cool place to prevent degradation, especially cocoa butter types.

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Packaging for Suppositories

Most are individually wrapped in foil or plastic to prevent contact and adhesion.

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Acidic pH in Vaginal Suppositories

Maintaining around pH 4.5 to discourage pathogens and support natural bacteria.

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Common Ingredients in Vaginal Tablets

They include lactose, starch, PVPP, and magnesium stearate for stability and disintegration.

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Effects of Humidity on Suppositories

High humidity can cause suppositories to become spongy, while dryness can make them brittle.

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Study Notes

Suppositories: Dosage Forms

  • Suppositories are solid dosage forms for insertion into body orifices.
  • They melt, soften, or dissolve to release local or systemic medication.
  • Common insertion sites are rectum, vagina, and urethra.

Suppository Shapes and Sizes

  • Suppository shapes and sizes vary based on intended use and content.
  • Shapes must allow for easy insertion and retention.
  • Rectal suppositories are typically cylindrical or bullet-shaped, often tapered.
  • Vaginal suppositories are usually globular, oviform, or cone-shaped.
  • Urethral suppositories are slender and pencil-shaped.
  • Size and weight vary by site (adult vs. infant/child).

Rectal Suppositories

  • Adult rectal suppositories are typically 32 mm long and 2g.
  • Infant/child rectal suppositories are smaller and half the weight.

Vaginal Suppositories

  • Vaginal suppositories (also called pessaries) are usually globular, oviform, or cone-shaped.
  • Typical weight is 5g when cocoa butter is the base.
  • Weights can vary based on base material and manufacture.

Urethral Suppositories

  • Urethral suppositories (bougies) are slender and pencil-shaped for male or female use.
  • Male suppositories are 3-6 mm in diameter and 140 mm in length.
  • Female suppositories are shorter and half the weight.
  • Used for antibacterial or local anesthetic purposes.

Fate of Suppository Base

  • The base softens, melts, or dissolves, releasing medication into surrounding tissues.
  • Medication can be retained locally or absorbed systemically.
  • Slow-release suppositories are also available, and morphine sulfate is a common example.

Local Rectal Suppositories

  • Commonly used to relieve constipation.
  • Glycerin suppositories cause laxation through mucosal irritation.
  • Other conditions include hemorrhoids and anoectal problems.
  • Anti-hemorrhoidal suppositories often contain anesthetics, vasoconstrictors, astringents, analgesics, and emollients.

Local Vaginal Suppositories

  • Commonly used for contraception, feminine hygiene, or treating infections.
  • Nonoxynol-9 is common in contraceptives.
  • Vaginal suppositories control infections like Trichomonas vaginalis and Candida albicans.

Systemic Effects of Rectal Suppositories

  • Rectal and vaginal mucous membranes can absorb many soluble drugs for systemic effects.
  • Rectal route offers advantages over oral administration:
  • Preserves drugs sensitive to stomach pH or enzymes.
  • Avoids stomach irritation.
  • Bypasses the liver (partial).
  • Convenient for patients unable or unwilling to swallow.
  • Effective for vomiting patients.
  • Prochlorperazine, indomethacin, and ondansetron are examples.

Factors Affecting Rectal Drug Absorption

  • Physiological factors like rectum volume (empty is best), colonic contents (diarrhea, obstruction), and vascularization impact absorption.
  • Physiochemical factors of the drug and base.

Rectal Absorption: Physiological Factors

  • The human rectum is ~15-20 cm long, containing 2-3 mL of mucous fluid when empty.
  • The rectum is not motile.
  • Ample vascularization helps absorption.
  • Rectal fluid pH is neutral (7), with no significant buffering.

Rectal Absorption: Physicochemical Factors

  • Drug solubility (lipid/water partition coefficient) influences base selection.
  • Lipophilic drugs absorb better from fatty bases.
  • Water-soluble drugs use water-soluble bases.
  • Particle size (fine particles dissolve faster), amount of drug, and pKa also matter.

Suppository Bases

  • Ideal suppository bases are non-toxic, compatible with drug, manufactureable, melt/dissolve at body temp., solidify easily, non-irritating, and stable.

Main Types of Suppository Bases

  • Fatty bases (oleaginous): cocoa butter, hydrogenated vegetable oils, and other fat-based compounds.
  • Water-soluble/miscible bases: glycerinated gelatin, polyethylene glycols (PEGs).
  • Miscellaneous bases: mixtures of lipophilic and hydrophilic substances.

Cocoa Butter (Theobroma Oil): Properties

  • A yellowish-white solid, derived from cocoa beans.
  • Melts at a temperature just below body temperature (30-36°C).
  • Shows polymorphism (existence in several crystalline forms) that affects melting/solidification process.

Cocoa Butter Polymorphism: Disadvantages

  • Polymorphism instability (beta crystal formation)
  • Adherence to molds
  • Low melting point
  • Poor water absorbance
  • Instability during storage
  • Warm climates can affect it

Other Fatty Bases

  • Various commercial fat-based bases are used, using combinations of materials for stability.

Glycerinated Gelatin Bases

  • A slow-softening base that is typically used in vaginal suppositories.
  • Hygroscopic; must be shielded from moisture.

Polyethylene Glycols (PEGs)

  • Various types of PEGs (300, 400, 600, etc.) may be mixed as suppository bases.
  • Do not melt at body temperature but dissolve slowly
  • Stable in warm weather and convenient to use
  • Should be dipped in water if not at least 20% water content.

Miscellaneous Bases

  • Surfactant mixtures(Polyoxyl 40 stearate), Mixtures of fatty bases + emulsifying agents to improve water-holding capacity.

Preparation Methods

  • Molding: The most common method (melt, mix, pour, cool).
  • Compression: Using machines that press the base and active pharmaceutical ingredients into the mold.
  • Hand rolling/shaping: Less common with modern tools' development.

Suppository Amount Calculation

  • The pharmacist calculates required amounts of base and active, accounting for drug volume, losses, and mold dimensions.

Medicated Suppositories: Considerations

  • Drug quantities less than 100 mg/2g are generally insignificant but larger quantities of active pharmaceutical ingredients require calculation.

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