revision_rectal_and_vaginal

Rectal Drug Delivery (RDD)

A method of administering medications via the rectum, often used when oral administration is not appropriate.

Suppository

Solid dosage forms intended for insertion into body orifices (rectum, vagina, urethra) where they melt, soften, or dissolve to exert effects.

First pass metabolism

The metabolic process that occurs in the liver, where the concentration of a drug is reduced before it reaches systemic circulation.

Ideal properties of a suppository base

Melts at 37ºC, solidifies quickly, easily molded, compatible with a variety of drugs, low acid value, non-toxic, non-irritant.

Fatty bases

Low melting suppository bases like cocoa butter that melt at body temperature, often used in rectal preparations.

Water-soluble bases

Suppository bases that are miscible with body fluids, like polyethylene glycol (PEG), offering different melting points and drug release properties.

Physiological factors affecting RDD

Factors such as colonic content, rectal fluid composition, circulation route, and the pH of the rectum that influence drug absorption.

Absorption characteristics of rectal administration

Absorption can be irregular/variable due to factors such as rectal volume and maintenance of contact with the rectal mucosa.

Potential advantages of RDD

Partial avoidance of first-pass metabolism, reasonable surface area for absorption, and accommodating large doses.

Microbiocides

Compounds or formulations designed to prevent the transmission of sexually transmitted infections and HIV.

Vaginal drug delivery systems (VDDS)

Methods used to deliver drugs via the vaginal route for either systemic or localized effects.

Pharmacological effect

The biochemical effect a drug has on the body, which can be local or systemic based on the delivery method.

Lipid-water partition coefficient

A measure of how a drug partitions between lipid and aqueous environments, which influences its absorption and efficacy.

Ideal vaginal dosage form characteristics

Ease of insertion, maintenance of pH close to vaginal pH, stability, non-irritation, and compatibility with other treatments.

Guidelines for extemporaneous compounding of suppositories

Factors to consider include drug solubility in the base, melting point, and ensuring uniformity of the final dosage form.

Examples of traditional vaginal dosage forms

Pessaries, vaginal tablets, ovules, and medicated tampons.

Current technologies in vaginal drug delivery

Delivery systems like creams, gels, pessaries, tablets, and IVRs that facilitate drug administration in the vaginal area.

pKa of a drug

The pH at which a drug is 50% ionized; affects its absorption through the rectal or vaginal mucosa.

Local versus systemic effects in VDDS

Local effects target specific sites, while systemic effects impact the entire body through absorption into the bloodstream.

Composition of vaginal fluids

Composed of mucus and transudate, influencing drug dissolution and absorption.

Enzymatic activity in the vaginal environment

Refers to the activity of enzymes which can affect drug stability and absorption.

Rectal Drug Delivery Strategies

Different approaches and techniques used to enhance the efficacy and absorption of drugs administered rectally.

Formulation considerations for suppositories

Factors such as active ingredient stability, base selection, and release profiles that influence suppository design.

Influence of rectal anatomy on drug absorption

Anatomical factors such as blood supply and mucosal surface area that play a role in drug absorption from the rectal cavity.

Compounding techniques for suppositories

Methods such as fusion, molding, or compression used in the preparation of suppositories for consistent quality.

Patient compliance with RDD

The adherence level of patients using rectal drug delivery systems, which may be affected by formulation characteristics and patient perception.

Comparison of rectal and oral routes

Differences in absorption, onset of action, and first-pass metabolism between rectal drug delivery and traditional oral administration.

Impact of pH on drug solubility in RDD

The significance of rectal pH on the solubility and absorption of various drugs during rectal administration.

Bioavailability in rectal vs. oral administration

The degree and rate at which a drug or active ingredient is absorbed into systemic circulation via rectal and oral routes.

Therapeutic uses of vaginal drug delivery

Applications of vaginal drug delivery systems for treating conditions such as infections, hormonal imbalances, and contraception.

Patient counseling points for VDDS

Key information to provide patients regarding the use, insertion, and expected effects of vaginal drug delivery systems.