Pharmaceuticals: Suppositories and Pessaries
48 Questions
3 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a characteristic of an ideal suppository base?

  • It should be stable on storage. (correct)
  • It should be highly irritating.
  • It must dissolve quickly in oil.
  • It should react strongly with medications.

How does the melting point of a suppository base affect drug release?

  • Melting point has no effect on drug action.
  • A melting point at body temperature promotes drug release. (correct)
  • A higher melting point increases absorption.
  • A lower melting point slows down drug action.

What can happen if a base interacts negatively with the drug?

  • Drug stability will improve.
  • The drug will be absorbed effectively.
  • Drug absorption can be impaired or prevented. (correct)
  • The base will always enhance the drug effect.

Which component is NOT a characteristic of fatty bases used in suppositories?

<p>Highly hydrophilic. (C)</p> Signup and view all the answers

What effect does an irritating base have on the digestive system?

<p>It can initiate a colonic response and cause bowel movement. (C)</p> Signup and view all the answers

Which type of base is Cocoa butter categorized as?

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

Why is it important for a suppository base to be easily molded?

<p>It facilitates manufacturing and allows easy removal from molds. (C)</p> Signup and view all the answers

What is a potential drawback of using a poorly designed suppository base?

<p>Incomplete drug release and absorption. (C)</p> Signup and view all the answers

Which of the following is a characteristic of hydrophilic bases?

<p>They dissolve rather than melt. (A)</p> Signup and view all the answers

What is a disadvantage of glycerogelatin bases?

<p>They may lead to rectal irritation. (D)</p> Signup and view all the answers

Which of the following is an example of a water-soluble base?

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

What is the primary component of the glycerol suppository base according to the BP standard?

<p>70 % (D)</p> Signup and view all the answers

What can happen due to the hygroscopic nature of glycerogelatin?

<p>Dehydration of rectal mucosa (A)</p> Signup and view all the answers

What is one important characteristic of an ideal glycerogelatin suppository?

<p>Non-gritty texture (D)</p> Signup and view all the answers

What is a risk associated with glycerogelatin suppositories?

<p>Unpredictable drug effect (D)</p> Signup and view all the answers

Why should glycerogelatin bases be stored in tight containers?

<p>To limit moisture absorption (B)</p> Signup and view all the answers

What is the approximate quantity of fluid available for drug dissolution in the rectum?

<p>3 ml (D)</p> Signup and view all the answers

What is the ideal characteristic of drugs used rectally regarding their solubility?

<p>High aqueous solubility (B)</p> Signup and view all the answers

What effect does particle size have on drug absorption in rectal administration?

<p>Smaller particles lead to faster dissolution (B)</p> Signup and view all the answers

How does the state of the rectum (full or empty) impact drug absorption?

<p>Empty rectum facilitates rapid absorption (C)</p> Signup and view all the answers

What is the role of the partition coefficient in drug absorption?

<p>Determines solubility in base and rectal fluid (A)</p> Signup and view all the answers

What is a characteristic of rectal fluids concerning pH?

<p>Neutral pH between 6.5 and 8 (A)</p> Signup and view all the answers

What happens to drug absorption when using slightly soluble drugs in the rectum?

<p>Absorption is slow due to dissolution being rate-limiting (A)</p> Signup and view all the answers

What effect does a full rectum have on drug absorption?

<p>Delays drug dissolution and absorption (D)</p> Signup and view all the answers

What happens to cacao butter suppositories when the percentage of solid exceeds 30%?

<p>They may become brittle. (A)</p> Signup and view all the answers

What is a recommended additive to reduce brittleness in cacao butter suppositories?

<p>Tween 80 (C)</p> Signup and view all the answers

What is the acceptable deviation for the weight of any suppository from the average weight?

<p>No more than 10% (A)</p> Signup and view all the answers

What should the drug content in each suppository not deviate from?

<p>90-110% of labeled content (A)</p> Signup and view all the answers

What temperature should the water bath be for the liquefaction time test?

<p>37° C (A)</p> Signup and view all the answers

What is the purpose of the breaking test for suppositories?

<p>To measure brittleness or fragility (D)</p> Signup and view all the answers

Which of the following characteristics should NOT be present in the appearance of suppositories?

<p>Air bubbles or cracks (D)</p> Signup and view all the answers

How many suppositories should be assayed for drug content uniformity?

<p>20 suppositories (B)</p> Signup and view all the answers

What is the main reason cocoa butter must be slowly melted over a warm water bath?

<p>To avoid the formation of unstable crystalline forms (A)</p> Signup and view all the answers

What happens if cocoa butter is quickly heated and then cooled suddenly?

<p>It forms unstable α or γ crystals (A)</p> Signup and view all the answers

What is a disadvantage of cocoa butter regarding its adherence to molds?

<p>It does not contract sufficiently on cooling (C)</p> Signup and view all the answers

What is the suitable melting point range of cocoa butter for it to remain solid?

<p>30-36 °C (B)</p> Signup and view all the answers

How do some drugs like phenol and chloral hydrate affect cocoa butter's melting point?

<p>They lower the melting point (A)</p> Signup and view all the answers

What agent can be added to cocoa butter to raise its melting point when certain drugs are present?

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

What is a potential issue with cocoa butter during storage?

<p>It may become rancid (D)</p> Signup and view all the answers

What method can help in reducing the sticking of cocoa butter suppositories to the mold?

<p>Using adequate soap lubrication (B)</p> Signup and view all the answers

What is a primary advantage of using soap glycerin for suppositories?

<p>It allows for a larger incorporation of glycerin. (C)</p> Signup and view all the answers

Which of the following is a disadvantage of soap glycerin in suppository formulation?

<p>It contributes to local tissue irritation. (C)</p> Signup and view all the answers

Why should water be avoided in suppository preparations?

<p>It can support bacterial and fungal growth. (D)</p> Signup and view all the answers

What factor affects the hygroscopicity of PEG bases?

<p>Chain length of the molecule. (C)</p> Signup and view all the answers

What issue can lead to brittleness in suppositories?

<p>Low viscosity during manufacturing. (C)</p> Signup and view all the answers

What can be added to increase the viscosity of suppositories if it is too low?

<p>Silica gel. (B)</p> Signup and view all the answers

What is a drawback of glycerogelatin suppositories in relation to humidity?

<p>They may absorb moisture in humid conditions. (B)</p> Signup and view all the answers

Which statement is true regarding the use of fat in suppository formulations?

<p>Fats accelerate drug crystallization at high temperatures. (B)</p> Signup and view all the answers

Flashcards

Rectal Fluid Quantity

The amount of fluid in the rectum is very small, approximately 3 ml. This limits how much drug can dissolve and be absorbed.

Rectal Drug Solubility

Drugs used rectally need to dissolve quickly in the rectal fluid for efficient absorption. They should have high aqueous solubility.

Rectal Fluid pH

The pH of rectal fluid is neutral (around 6.5-8) and doesn't have much buffering capacity. This means that drugs need to be stable in this pH range.

Empty Rectum - Absorption

If the rectum is empty, the drug will be in direct contact with the absorbing surface, leading to rapid absorption and a quick onset of action.

Signup and view all the flashcards

Full Rectum - Absorption

A full rectum delays drug dissolution and absorption, making the onset of action slower.

Signup and view all the flashcards

Partition Coefficient

The ability of a drug to move between the base (like a suppository) and the rectal fluid. Highly soluble in base = slow release and absorption.

Signup and view all the flashcards

Particle Size

The smaller the particle size of a drug, the faster it dissolves and the quicker it is absorbed. This applies to undissolved drugs in suppositories.

Signup and view all the flashcards

Base Properties

The chemical nature of the base used in a suppository affects the release of the drug and its absorption. The base needs to be compatible with the drug.

Signup and view all the flashcards

Base Dissolution

A suppository base must melt, soften, or dissolve in the body to release the drug. The rate of this process directly affects how quickly the drug is absorbed.

Signup and view all the flashcards

Base-Drug Interaction

If a base reacts with the drug and prevents it from being released, the drug cannot be absorbed. The drug's effectiveness is compromised.

Signup and view all the flashcards

Irritating Base

A base that irritates the lining of the rectum can cause a bowel movement before the drug is fully absorbed. This leads to reduced effectiveness.

Signup and view all the flashcards

Non-Toxic and Non-Irritant

Ideally, a suppository base should not be poisonous or cause irritation. This ensures safety for the user.

Signup and view all the flashcards

Base Inertness

The base shouldn't react with the drug or change its properties. Maintaining the drug's form and effectiveness is crucial.

Signup and view all the flashcards

Melting or Dissolving Base

The base should melt or dissolve at body temperature, allowing the drug to be released efficiently.

Signup and view all the flashcards

Drug Release from Base

A good base allows the drug to be released easily and quickly, maximizing absorption.

Signup and view all the flashcards

Base Stability

The chosen base should be stable to prevent changes in its physical and chemical properties over time.

Signup and view all the flashcards

Polymorphism of Cocoa Butter

Cocoa butter can solidify into different crystal forms (alpha, beta, gamma) depending on the melting temperature and cooling rate. The stable beta form has a melting point of 30-36°C, while the unstable forms melt at lower temperatures.

Signup and view all the flashcards

Adherence to the Mold

Cocoa butter doesn't shrink enough when cooling, leading to suppositories sticking to the mold.

Signup and view all the flashcards

Softening Point of Cocoa Butter

Cocoa butter melts at 30-36 °C, which is too low for hot climates, making it unsuitable for tropical countries.

Signup and view all the flashcards

Lowering Melting Point by Drugs

Some drugs, like phenol and chloral hydrate, can lower the melting point of cocoa butter, making suppositories melt prematurely.

Signup and view all the flashcards

Raising Melting Point by Drugs

Drugs like lead acetate can raise the melting point of cocoa butter, preventing it from melting at body temperature.

Signup and view all the flashcards

Compensating Melting Point Changes

To compensate for the melting point change caused by drugs, additives like beeswax (for lowering) or castor oil (for raising) can be used.

Signup and view all the flashcards

Rancidity of Cocoa Butter

Cocoa butter can become rancid over time due to exposure to air and light.

Signup and view all the flashcards

Miscibility of Cocoa Butter

Cocoa butter is compatible with a wide range of ingredients, making it a versatile base for suppositories.

Signup and view all the flashcards

Hydrophilic Suppository Bases

Suppository bases that dissolve in rectal fluids, releasing medication through dissolution.

Signup and view all the flashcards

Glycerogelatin Base

A type of hydrophilic suppository base made from gelatin and glycerin, used for its dissolving properties.

Signup and view all the flashcards

PEG (Macrogol) Base

A type of hydrophilic suppository base made from polyethylene glycol (PEG), known for its water solubility.

Signup and view all the flashcards

Soap Glycerin Base

A type of hydrophilic suppository base made from a combination of soap and glycerin, notable for its solubility in water.

Signup and view all the flashcards

Laxative Effect of Glycerogelatin Bases

The unwanted effect of glycerogelatin bases drawing water from the rectum, leading to bowel movements.

Signup and view all the flashcards

Rectal Irritation of Glycerogelatin Bases

The potential irritation caused by glycerogelatin bases when their hygroscopic nature dehydrates the rectal mucosa.

Signup and view all the flashcards

Unpredictable Dissolution Time of Glycerogelatin

The variable time it takes for glycerogelatin bases to dissolve, affecting drug release and therapeutic effect.

Signup and view all the flashcards

Microbial Contamination Risk of Glycerogelatin

The risk of microbial contamination associated with glycerogelatin suppository bases, due to their water-soluble nature.

Signup and view all the flashcards

Glycerogelatin suppositories

A type of suppository base made from glycerol and gelatin. It often contains a high percentage of glycerol for its laxative properties.

Signup and view all the flashcards

Soap Glycerin suppositories

A suppository base made by combining stearic acid and sodium carbonate in a glycerin solution, resulting in sodium stearate, commonly known as stearin soap.

Signup and view all the flashcards

Hygroscopicity

A property of certain substances, including some suppository bases, to absorb moisture from the surrounding environment. It can cause issues like irritation and formulation breakdown.

Signup and view all the flashcards

Water in suppositories

Water can lead to issues like oxidation of fats, fungal growth, drug degradation, and unwanted reactions within a suppository. It can also cause drug crystallization if it evaporates during manufacturing.

Signup and view all the flashcards

Viscosity in suppositories

A measure of a liquid's resistance to flow. In suppositories, low viscosity can lead to uneven drug distribution, so suspending agents like silica gel are often used.

Signup and view all the flashcards

Brittleness in suppositories

Brittle suppositories are prone to breaking easily, making them difficult to manage, package, and use.

Signup and view all the flashcards

PEG (Macrogol) base suppositories

Polyethylene glycol (PEG) is a type of synthetic polymer used in suppositories. It's known for its hygroscopicity, which can vary depending on the polyethylene glycol's molecular weight.

Signup and view all the flashcards

Hydrophilic

The tendency of substances to attract water molecules. This is often seen in suppositories, where water absorption can lead to problems like irritation and formulation breakdown.

Signup and view all the flashcards

Cacao Butter Brittle?

Cacao butter suppositories can become brittle if the percentage of solid fats is too high (above 30%).

Signup and view all the flashcards

Fixing Cacao Butter Brittleness

To prevent brittleness, a small amount (2%) of a substance like Tween 80, caster oil, glycerin, or PEG can be added to the cacao butter to make the suppository more flexible.

Signup and view all the flashcards

Weight Uniformity Test

The uniformity of suppository weights is tested by weighing each suppository individually and then by weighing all the suppositories together. The average weight is calculated, and the deviation of individual weights from this average is compared to accepted limits.

Signup and view all the flashcards

Weight Uniformity Limits

No more than 2 suppositories out of 20 should deviate by more than 5 percent from the average weight, and none should deviate by more than 10 percent.

Signup and view all the flashcards

Drug Content Uniformity Test

The drug content of 20 suppositories is tested to ensure that the amount of drug in each suppository is within an acceptable range. The drug content in each suppository should be between 90-110% of the labeled amount.

Signup and view all the flashcards

Liquefaction Time Test

This test measures the time it takes for a suppository to melt completely when placed into a 37°C bath. The suppository is submerged and the time it takes to melt or dissolve is recorded.

Signup and view all the flashcards

Breaking Test (Hardness)

This test assesses the fragility or brittleness of a suppository. The suppository is subjected to a force to measure its resistance to breaking.

Signup and view all the flashcards

Stability Test

A stability test examines how well a suppository maintains its physical and chemical properties over time. This includes its appearance, drug content, and melting point.

Signup and view all the flashcards

Study Notes

Suppositories and Pessaries

  • Suppositories are medicated, molded solid dosage forms of various sizes and shapes designed for insertion into body cavities (rectum, vagina, or urethra).
  • Suppositories are inserted into the rectum.
  • Pessaries are inserted into the vagina.

Types of Suppositories

  • Rectal suppositories: conical or torpedo shape, ~2-3 cm length.
    • Adult dose: ~2 gm
    • Child dose: ~1 gm
  • Urethral suppositories (Bougies): cylindrical or tube shape in globular or oval form, ~3-6 mm diameter.
    • Adult dose: ~4 gm
    • Child dose: No data given
  • Vaginal suppositories (pessaries): cylindrical or tube shape in globular (ball), oval or cone-shaped, ~4-5 gm in weight.

Action of Suppositories

  • When inserted into the body, suppositories and pessaries either melt, soften, or dissolve, and exert a local or systemic effect.

Advantages of Suppositories

  • Local effect:
    • Treat infections, pain and inflammation (e.g., hemorrhoids, vaginal fungal infections).
    • Relieve constipation.
    • Treat diseases of the colon (e.g., ulcerative colitis).
  • Systemic effect:
    • For babies or elderly unable to swallow oral medication.
    • Post-operative patients.
    • People with nausea or vomiting.
    • Drugs irritating to the stomach.
    • Drugs destroyed by the pH or enzymatic activity of the stomach or intestine
    • Drugs destroyed by portal circulation (bypass first-pass metabolism)

Disadvantages of Suppositories

  • Inconvenient: Not favored by patients, especially children; some suppositories leak or are expelled.
  • Rectal absorption: Slow, irregular, and unpredictable.
  • Mucosal irritation: Caused by some drugs or bases.
  • Manufacturing/Storage costs: Higher than other drug forms.

Physiology of the Rectum

  • The rectum is ~15-20 cm in length, with 1.5-3 ml of fluids.
  • The pH is ~6.8.

Absorption of Drugs from the Rectum

  • 50-70% of drugs absorbed directly into the bloodstream via hemorrhoidal veins, bypassing the liver's first-pass metabolism.
  • Route of absorption differs based on inferior vs. superior hemorrhoidal veins.

Factors Affecting Rectal Absorption

  • Physiological factors:
    • Site of insertion.
    • Route of absorption and circulation.
    • Quantity of rectal fluid.
    • Properties of rectal fluid.
    • Contents of the rectum.
  • Physicochemical factors:
    • Partition coefficient.
    • Particle size.
    • Nature of the base.

Properties of Rectal Fluids

  • Neutral pH (6.5-8).
  • No buffer capacity.

Contents of the Rectum (Empty vs. Full)

  • Empty rectum: Rapid drug absorption, rapid onset of action.
  • Full rectum: Slower drug absorption, delayed onset of action.

Physicochemical Factors Affecting Absorption

  • Drug solubility: Drugs highly soluble in the base will have slow release into rectal fluids, resulting in slow absorption; conversely, high solubility in rectal fluids leads to faster and more rapid absorption.
  • Particle size: Smaller particle size leads to faster dissolution and faster absorption.
  • Base properties: The ability of the base to melt, soften or dissolve will determine release rate of the drug leading to a faster or slower rate of drug action.
    • Base interactions with the drug will impair or even prevent drug absorption.
    • Bases which irritate mucous membranes will initiate a colonic response and bowel movement; incomplete drug release and absorption.

Ideal Suppository Bases

  • Non-toxic and non-irritant.
  • Inert and compatible with the drug.
  • Melts or softens at body temperature or dissolves in body fluids.
  • Readily releases the drug.
  • Easily molded and removed from the mold.
  • Stable to heating above the melting point.
  • Stable on storage.
  • Easy to handle.

Types of Suppository Bases

  • Fatty (Oleaginous/Hydrophobic): Cocoa butter, semi-synthetic fats. Melt at body temperature.
  • Hydrophilic (Water-Miscible/Water-Soluble): Glycerogelatin, PEG (Polyethylene Glycol), sorbitol, soap glycerin. Dissolve rather than melt at body temperature.

Cocoa Butter (A-Type)

  • Benefits: Solid at room temperature but melts at body temperature, miscible with many ingredients, non-irritating, non-toxic.
  • Drawbacks: Polymorphism (different crystalline forms depending on cooling rate).
  • Additional notes: Adherence to the mold; softening point may be too low for hot climates, requiring refrigeration during storage, melting point may be lowered by some drugs, or raised by others, rancidity on storage.

Cocoa Butter Substitutes (B-Type)

  • Benefits: Unaffected by overheating, low level of unsaturated fatty acids, good resistance to oxidation (preventing rancidity).
  • Drawbacks: More expensive, Brittle, can be challenging to handle, wrap, and use; greater risk of drug particles sedimenting during preparation, potentially causing localized irritation, requiring refrigeration for preparation and handling.

Hydrophilic Bases

  • Benefits: No laxative effect, less microbial contamination, melting points are typically above body temperature.
  • Drawbacks: Very hygroscopic (absorb water), requiring special packaging and storage, potentially lowers drug bioavailability by binding drugs in the base, potentially incompatible with certain drug types and/or packaging materials.

Problems in Formulation and Storage

  • Water: Should be avoided in suppositories, as it can increase the oxidation of fats and create bacterial/fungal growth, increase degradation rate of drugs, and cause reactions. If water evaporates, the drugs might recrystalize.
  • Hygroscopicity: Glycerin and PEG are hygroscopic.
  • Viscosity: Low viscosity may require additives for uniform dispersion of the drug.
  • Brittleness: Some substances can be brittle if cooled rapidly; additional components can prevent brittleness.

Suppository Evaluation and Quality Control

  • Appearance: Uniformity in size, shape, and color; no cracks or pits.
  • Weight uniformity: Compare individual weights to the average weight; no significant differences.
  • Drug content uniformity: Assesses the drug content in each suppository, comparing the results with the labelled drug content.
  • Liquefaction Time: Measures the time it takes for the suppository to fully melt or disperse in a constant temperature water bath.
  • Breaking Test: Measures the suppository's hardness and resistance to breaking.
  • Dissolution test: Measures the rate at which the drug dissolves.
  • Stability test: Assesses the long-term storage stability of the suppositories.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Suppositories Lecture Notes PDF

Description

This quiz covers the essential information about suppositories and pessaries, including their types, uses, and advantages. Learn how these medicated forms function and their applications in treating various conditions. Test your knowledge on dosage and administration.

More Like This

Suppositories: Dosage Forms Quiz
5 questions

Suppositories: Dosage Forms Quiz

AthleticResilience5188 avatar
AthleticResilience5188
Pessaries: Vaginal Suppositories Quiz
10 questions

Pessaries: Vaginal Suppositories Quiz

SublimeIris avatar
SublimeIris
Pharmaceuticals: Suppositories Overview
90 questions

Pharmaceuticals: Suppositories Overview

AttentiveDatePalm avatar
AttentiveDatePalm
Pharmacology: Suppositories Overview
43 questions

Pharmacology: Suppositories Overview

BlitheGallium avatar
BlitheGallium
Use Quizgecko on...
Browser
Open
Browser
Browser